Content reports ported from DSpace 6.x (#8598)

* content Reports

* Fixed CheckStyle errors

* Fixed CheckStyle errors

* Fixed CheckStyle errors

* First batch of fixes: mainly Javadoc, and a bit of code re-engineering

* Fixed CheckStyle errors

* Fixed CheckStyle errors in dspace-server-webapp

* Applied requested changes for DSpace code conventions compliance

* Added GET endpoint to Filtered Items report

* Updated to latest version from main branch

* Fixed missing imports

* Fixed CheckStyle errors

* Fixed H2 database initialization

* Fixed unit tests and an integration test

* Fixed CheckStyle errors

* Fixed CheckStyle errors

* Fixed ItemServiceIT test

* Test without collection criterion

* Fixed max result count in integration test

* Disable findByMetadataQuery test to diagnose errors in other tests

* Disabled ContentReportRestRepositoryIT test to validate existing tests

* Re-enable test in dspace-api

* Re-enabled ContentReportRestRepositoryIT tests to diagnose failures

* Fixed item matching in the second test

* Fixed JSON path error

* Use projections to trigger embedding the owning collection in ItemRest only for the Filtered Items report

* Fixed usage of allowEmbedding() through non-null arguments

* Exclude owning collection from ItemRest when null/empty

* Trying an alternate way to discriminate report-based Item conversions

* Fixed embedded owning collection management

* Replaced ItemConverter with correct version

* Fixed Filtered Collections test in ContentReportRestRepositoryIT

* Fixed test

* Transferred owning collection to a separate class FilteredItemRest

* Rollback to DSpace repo version

* Fixed matcher for Filtered Collections summary

* Fixed matcher for Filtered Collections summary (take 2)

* Add printing mock request results to diagnose remaining problems

* Try logging output through System.err

* Cancelled attempt to print JSON results (does nothing)

* Attempt to fix ContentReportRestRepositoryIT tests

* Removed predefined UUIDs and handles

* Fixed import formatting

* Fixed expected results in ContentReportRestRepositoryIT

* Switched to a custom matcher for the Filtered Item report test

* Fixed import format

* Fixed JSON collection matching in Filtered Items test

* Fixed Filtered Items matcher

* Fixed expected result

* Fixed the test for now...

* Fixed test again

* Disabled non-working test

* Fixed a few typos

* Moved Filtered Collections report business logic to dspace-api

* Fixed outdated controller

* Fixed import and lost @Ignore annotation

* Retrieved a lost test correction

* Fixed Filtered Collections test

* Reverted to the last working version (except for 2nd test, which remains
disabled)

* Moved Filtered Items report business logic to dspace-api

* Fixed import style

* Added switch to enable/disable Content Reports

* Fixed an out-of-date class

* Removed unused imports

* Fixed activation configuration for Content Reports

* Added missing @Test annotation

* A forgotten Hibernate dialect configuration. I also removed obsolete
Oracle settings configuration.

* Switched to GET requests for Content Reports

* Switched to GET requests for Content Reports

* Fixed styling in imports

* Fixed imports

* Cleaned deprecated code

* Simplified regex since trim() method is invoked on each token thereafter

* Added Javadoc in the interface.

* Relocated Content Reports configuration into a new file

* Added "unauthorized" tests and cleaned up code repetitions

* Fixed parameter according to Javadoc

* Fixed Filtered Items test

* Use of @ConditionalOnProperty annotation

* Rolled back to manual parameter managing

* Second try on @ConditionalOnProperty, with proper test configuration

* Rolled back (again) to manual service activation checking (needed for
proper behaviour depending on activation and authorization)

* Eliminated inheritance between FilteredItemRest and ItemRest

* Re-established the type property in FilteredItemRest (and in
FilterCollectionRest for uniformity).

---------

Co-authored-by: Jean-François Morin <jean-francois.morin@bibl.ulaval.ca>

dspace-api/src/main/java/org/dspace/content/ItemServiceImpl.java

@@ -49,6 +49,7 @@ import org.dspace.content.service.MetadataSchemaService;
 import org.dspace.content.service.RelationshipService;
 import org.dspace.content.service.WorkspaceItemService;
 import org.dspace.content.virtual.VirtualMetadataPopulator;
+import org.dspace.contentreport.QueryPredicate;
 import org.dspace.core.Constants;
 import org.dspace.core.Context;
 import org.dspace.core.LogHelper;
@@ -175,7 +176,6 @@ public class ItemServiceImpl extends DSpaceObjectServiceImpl<Item> implements It
     private QAEventsDAO qaEventsDao;
 
     protected ItemServiceImpl() {
-        super();
     }
 
     @Override
@@ -275,9 +275,8 @@ public class ItemServiceImpl extends DSpaceObjectServiceImpl<Item> implements It
                                               + template.getID()));
 
             return template;
-        } else {
-            return collection.getTemplateItem();
         }
+        return collection.getTemplateItem();
     }
 
     @Override
@@ -1190,9 +1189,8 @@ public class ItemServiceImpl extends DSpaceObjectServiceImpl<Item> implements It
         if (item.getOwningCollection() == null) {
             if (!isInProgressSubmission(context, item)) {
                 return true;
-            } else {
-                return false;
             }
+            return false;
         }
 
         return collectionService.canEditBoolean(context, item.getOwningCollection(), false);
@@ -1284,8 +1282,8 @@ prevent the generation of resource policy entry values with null dspace_object a
             if (!authorizeService
                 .isAnIdenticalPolicyAlreadyInPlace(context, dso, defaultPolicy.getGroup(), Constants.READ,
                     defaultPolicy.getID()) &&
-                   (!appendMode && this.isNotAlreadyACustomRPOfThisTypeOnDSO(context, dso) ||
+                   (!appendMode && isNotAlreadyACustomRPOfThisTypeOnDSO(context, dso) ||
-                    appendMode && this.shouldBeAppended(context, dso, defaultPolicy))) {
+                    appendMode && shouldBeAppended(context, dso, defaultPolicy))) {
                 ResourcePolicy newPolicy = resourcePolicyService.clone(context, defaultPolicy);
                 newPolicy.setdSpaceObject(dso);
                 newPolicy.setAction(Constants.READ);
@@ -1384,9 +1382,8 @@ prevent the generation of resource policy entry values with null dspace_object a
 
         if (Item.ANY.equals(value)) {
             return itemDAO.findByMetadataField(context, mdf, null, true);
-        } else {
-            return itemDAO.findByMetadataField(context, mdf, value, true);
         }
+        return itemDAO.findByMetadataField(context, mdf, value, true);
     }
 
     @Override
@@ -1430,9 +1427,24 @@ prevent the generation of resource policy entry values with null dspace_object a
 
         if (Item.ANY.equals(value)) {
             return itemDAO.findByMetadataField(context, mdf, null, true);
-        } else {
-            return itemDAO.findByMetadataField(context, mdf, value, true);
         }
+        return itemDAO.findByMetadataField(context, mdf, value, true);
+    }
+
+    @Override
+    public List<Item> findByMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids, long offset, int limit)
+            throws SQLException {
+        return itemDAO.findByMetadataQuery(context, queryPredicates, collectionUuids, "text_value ~ ?",
+                offset, limit);
+    }
+
+
+    @Override
+    public long countForMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids)
+            throws SQLException {
+        return itemDAO.countForMetadataQuery(context, queryPredicates, collectionUuids, "text_value ~ ?");
     }
 
     @Override
@@ -1498,20 +1510,19 @@ prevent the generation of resource policy entry values with null dspace_object a
         Collection ownCollection = item.getOwningCollection();
         if (ownCollection != null) {
             return ownCollection;
-        } else {
-            InProgressSubmission inprogress = ContentServiceFactory.getInstance().getWorkspaceItemService()
-                                                                   .findByItem(context,
-                                                                               item);
-            if (inprogress == null) {
-                inprogress = WorkflowServiceFactory.getInstance().getWorkflowItemService().findByItem(context, item);
-            }
-
-            if (inprogress != null) {
-                return inprogress.getCollection();
-            }
-            // is a template item?
-            return item.getTemplateItemOf();
         }
+        InProgressSubmission inprogress = ContentServiceFactory.getInstance().getWorkspaceItemService()
+                                                               .findByItem(context,
+                                                                           item);
+        if (inprogress == null) {
+            inprogress = WorkflowServiceFactory.getInstance().getWorkflowItemService().findByItem(context, item);
+        }
+
+        if (inprogress != null) {
+            return inprogress.getCollection();
+        }
+        // is a template item?
+        return item.getTemplateItemOf();
     }
 
     @Override
@@ -1611,9 +1622,8 @@ prevent the generation of resource policy entry values with null dspace_object a
         try {
             if (StringUtils.isNumeric(id)) {
                 return findByLegacyId(context, Integer.parseInt(id));
-            } else {
-                return find(context, UUID.fromString(id));
             }
+            return find(context, UUID.fromString(id));
         } catch (IllegalArgumentException e) {
             // Not a valid legacy ID or valid UUID
             return null;

dspace-api/src/main/java/org/dspace/content/dao/ItemDAO.java

@@ -11,11 +11,13 @@ import java.sql.SQLException;
 import java.util.Date;
 import java.util.Iterator;
 import java.util.List;
+import java.util.UUID;
 
 import org.dspace.content.Collection;
 import org.dspace.content.Community;
 import org.dspace.content.Item;
 import org.dspace.content.MetadataField;
+import org.dspace.contentreport.QueryPredicate;
 import org.dspace.core.Context;
 import org.dspace.eperson.EPerson;
 
@@ -27,12 +29,11 @@ import org.dspace.eperson.EPerson;
  * @author kevinvandevelde at atmire.com
  */
 public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
-    public Iterator<Item> findAll(Context context, boolean archived) throws SQLException;
+    Iterator<Item> findAll(Context context, boolean archived) throws SQLException;
 
-    public Iterator<Item> findAll(Context context, boolean archived, int limit, int offset) throws SQLException;
+    Iterator<Item> findAll(Context context, boolean archived, int limit, int offset) throws SQLException;
 
-    @Deprecated
+    @Deprecated Iterator<Item> findAll(Context context, boolean archived, boolean withdrawn) throws SQLException;
-    public Iterator<Item> findAll(Context context, boolean archived, boolean withdrawn) throws SQLException;
 
     /**
      * Find all items that are:
@@ -45,7 +46,7 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return iterator over all regular items.
      * @throws SQLException if database error.
      */
-    public Iterator<Item> findAllRegularItems(Context context) throws SQLException;
+    Iterator<Item> findAllRegularItems(Context context) throws SQLException;
 
     /**
      * Find all Items modified since a Date.
@@ -55,10 +56,10 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return iterator over items
      * @throws SQLException if database error
      */
-    public Iterator<Item> findByLastModifiedSince(Context context, Date since)
+    Iterator<Item> findByLastModifiedSince(Context context, Date since)
         throws SQLException;
 
-    public Iterator<Item> findBySubmitter(Context context, EPerson eperson) throws SQLException;
+    Iterator<Item> findBySubmitter(Context context, EPerson eperson) throws SQLException;
 
     /**
      * Find all the items by a given submitter. The order is
@@ -70,19 +71,40 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return an iterator over the items submitted by eperson
      * @throws SQLException if database error
      */
-    public Iterator<Item> findBySubmitter(Context context, EPerson eperson, boolean retrieveAllItems)
+    Iterator<Item> findBySubmitter(Context context, EPerson eperson, boolean retrieveAllItems)
         throws SQLException;
 
-    public Iterator<Item> findBySubmitter(Context context, EPerson eperson, MetadataField metadataField, int limit)
+    Iterator<Item> findBySubmitter(Context context, EPerson eperson, MetadataField metadataField, int limit)
         throws SQLException;
 
-    public Iterator<Item> findByMetadataField(Context context, MetadataField metadataField, String value,
+    Iterator<Item> findByMetadataField(Context context, MetadataField metadataField, String value,
                                               boolean inArchive) throws SQLException;
 
-    public Iterator<Item> findByAuthorityValue(Context context, MetadataField metadataField, String authority,
+    /**
+     * Returns all the Items that belong to the specified aollections (if any)
+     * and match the provided predicates.
+     * @param context The relevant DSpace context
+     * @param queryPredicates List of predicates that returned items are required to match
+     * @param collectionUuids UUIDs of the collections to search.
+     *        If none are provided, the entire repository will be searched.
+     * @param regexClause Syntactic expression used to query the database using a regular expression
+     *        (e.g.: "text_value ~ ?")
+     * @param offset The offset for the query
+     * @param limit Maximum number of items to return
+     * @return A list containing the items that match the provided criteria
+     * @throws SQLException if something goes wrong
+     */
+    List<Item> findByMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+                                          List<UUID> collectionUuids, String regexClause,
+                                          long offset, int limit) throws SQLException;
+
+    long countForMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids, String regexClause) throws SQLException;
+
+    Iterator<Item> findByAuthorityValue(Context context, MetadataField metadataField, String authority,
                                                boolean inArchive) throws SQLException;
 
-    public Iterator<Item> findArchivedByCollection(Context context, Collection collection, Integer limit,
+    Iterator<Item> findArchivedByCollection(Context context, Collection collection, Integer limit,
                                                    Integer offset) throws SQLException;
 
     /**
@@ -95,7 +117,7 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return              An iterator containing the items for which the constraints hold true
      * @throws SQLException If something goes wrong
      */
-    public Iterator<Item> findArchivedByCollectionExcludingOwning(Context context, Collection collection, Integer limit,
+    Iterator<Item> findArchivedByCollectionExcludingOwning(Context context, Collection collection, Integer limit,
                                                                   Integer offset) throws SQLException;
 
     /**
@@ -106,11 +128,11 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return              The total amount of items that fit the constraints
      * @throws SQLException If something goes wrong
      */
-    public int countArchivedByCollectionExcludingOwning(Context context, Collection collection) throws SQLException;
+    int countArchivedByCollectionExcludingOwning(Context context, Collection collection) throws SQLException;
 
-    public Iterator<Item> findAllByCollection(Context context, Collection collection) throws SQLException;
+    Iterator<Item> findAllByCollection(Context context, Collection collection) throws SQLException;
 
-    public Iterator<Item> findAllByCollection(Context context, Collection collection, Integer limit, Integer offset)
+    Iterator<Item> findAllByCollection(Context context, Collection collection, Integer limit, Integer offset)
         throws SQLException;
 
     /**
@@ -123,7 +145,7 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return item count
      * @throws SQLException if database error
      */
-    public int countItems(Context context, Collection collection, boolean includeArchived, boolean includeWithdrawn)
+    int countItems(Context context, Collection collection, boolean includeArchived, boolean includeWithdrawn)
         throws SQLException;
 
     /**
@@ -139,7 +161,7 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return item count
      * @throws SQLException if database error
      */
-    public int countItems(Context context, List<Collection> collections, boolean includeArchived,
+    int countItems(Context context, List<Collection> collections, boolean includeArchived,
                           boolean includeWithdrawn) throws SQLException;
 
     /**
@@ -153,7 +175,7 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return iterator over items
      * @throws SQLException if database error
      */
-    public Iterator<Item> findAll(Context context, boolean archived,
+    Iterator<Item> findAll(Context context, boolean archived,
                                   boolean withdrawn, boolean discoverable, Date lastModified)
         throws SQLException;
 
@@ -187,7 +209,7 @@ public interface ItemDAO extends DSpaceObjectLegacySupportDAO<Item> {
      * @return count of items
      * @throws SQLException if database error
      */
-    public int countItems(Context context, EPerson submitter, boolean includeArchived, boolean includeWithdrawn)
+    int countItems(Context context, EPerson submitter, boolean includeArchived, boolean includeWithdrawn)
         throws SQLException;
 
 }

dspace-api/src/main/java/org/dspace/content/dao/impl/ItemDAOImpl.java

@@ -8,25 +8,36 @@
 package org.dspace.content.dao.impl;
 
 import java.sql.SQLException;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
 import java.util.Iterator;
 import java.util.List;
+import java.util.UUID;
 import javax.persistence.Query;
 import javax.persistence.TemporalType;
 import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaBuilder.In;
 import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.Predicate;
 import javax.persistence.criteria.Root;
+import javax.persistence.criteria.Subquery;
 
 import org.apache.logging.log4j.Logger;
 import org.dspace.content.Collection;
+import org.dspace.content.DSpaceObject_;
 import org.dspace.content.Item;
 import org.dspace.content.Item_;
 import org.dspace.content.MetadataField;
+import org.dspace.content.MetadataValue;
+import org.dspace.content.MetadataValue_;
 import org.dspace.content.dao.ItemDAO;
+import org.dspace.contentreport.QueryOperator;
+import org.dspace.contentreport.QueryPredicate;
 import org.dspace.core.AbstractHibernateDSODAO;
 import org.dspace.core.Context;
 import org.dspace.eperson.EPerson;
+import org.dspace.util.JpaCriteriaBuilderKit;
 
 /**
  * Hibernate implementation of the Database Access Object interface class for the Item object.
@@ -39,7 +50,6 @@ public class ItemDAOImpl extends AbstractHibernateDSODAO<Item> implements ItemDA
     private static final Logger log = org.apache.logging.log4j.LogManager.getLogger(ItemDAOImpl.class);
 
     protected ItemDAOImpl() {
-        super();
     }
 
     @Override
@@ -163,6 +173,105 @@ public class ItemDAOImpl extends AbstractHibernateDSODAO<Item> implements ItemDA
         return iterate(query);
     }
 
+    @Override
+    public List<Item> findByMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids, String regexClause, long offset, int limit) throws SQLException {
+        CriteriaBuilder criteriaBuilder = getCriteriaBuilder(context);
+        CriteriaQuery<Item> criteriaQuery = getCriteriaQuery(criteriaBuilder, Item.class);
+        Root<Item> itemRoot = criteriaQuery.from(Item.class);
+        criteriaQuery.select(itemRoot);
+        List<Predicate> predicates = toPredicates(criteriaBuilder, criteriaQuery, itemRoot,
+                queryPredicates, collectionUuids, regexClause);
+        criteriaQuery.where(criteriaBuilder.and(predicates.stream().toArray(Predicate[]::new)));
+        criteriaQuery.orderBy(criteriaBuilder.asc(itemRoot.get(DSpaceObject_.id)));
+        criteriaQuery.groupBy(itemRoot.get(DSpaceObject_.id));
+        try {
+            return list(context, criteriaQuery, false, Item.class, limit, (int) offset);
+        } catch (Exception e) {
+            e.printStackTrace();
+            throw e;
+        }
+    }
+
+    @Override
+    public long countForMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids, String regexClause) throws SQLException {
+        // Build the query infrastructure
+        CriteriaBuilder criteriaBuilder = getCriteriaBuilder(context);
+        CriteriaQuery<Item> criteriaQuery = getCriteriaQuery(criteriaBuilder, Item.class);
+        // Select
+        Root<Item> itemRoot = criteriaQuery.from(Item.class);
+        // Apply the selected predicates
+        List<Predicate> predicates = toPredicates(criteriaBuilder, criteriaQuery, itemRoot,
+                queryPredicates, collectionUuids, regexClause);
+        criteriaQuery.where(criteriaBuilder.and(predicates.stream().toArray(Predicate[]::new)));
+        // Execute the query
+        return countLong(context, criteriaQuery, criteriaBuilder, itemRoot);
+    }
+
+    private <T> List<Predicate> toPredicates(CriteriaBuilder criteriaBuilder, CriteriaQuery<T> query,
+            Root<Item> root, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids, String regexClause) {
+        List<Predicate> predicates = new ArrayList<>();
+
+        if (!collectionUuids.isEmpty()) {
+            Subquery<Collection> scollQuery = query.subquery(Collection.class);
+            Root<Collection> collRoot = scollQuery.from(Collection.class);
+            In<UUID> inColls = criteriaBuilder.in(collRoot.get(DSpaceObject_.ID));
+            collectionUuids.forEach(inColls::value);
+            scollQuery.select(collRoot.get(DSpaceObject_.ID))
+                    .where(criteriaBuilder.and(
+                            criteriaBuilder.equal(collRoot.get(DSpaceObject_.ID),
+                                    root.get(Item_.OWNING_COLLECTION).get(DSpaceObject_.ID)),
+                            collRoot.get(DSpaceObject_.ID).in(collectionUuids)
+                    ));
+            predicates.add(criteriaBuilder.exists(scollQuery));
+        }
+
+        for (int i = 0; i < queryPredicates.size(); i++) {
+            QueryPredicate predicate = queryPredicates.get(i);
+            QueryOperator op = predicate.getOperator();
+            if (op == null) {
+                log.warn("Skipping Invalid Operator: null");
+                continue;
+            }
+
+            if (op.getUsesRegex()) {
+                if (regexClause.isEmpty()) {
+                    log.warn("Skipping Unsupported Regex Operator: " + op);
+                    continue;
+                }
+            }
+
+            List<Predicate> mvPredicates = new ArrayList<>();
+            Subquery<MetadataValue> mvQuery = query.subquery(MetadataValue.class);
+            Root<MetadataValue> mvRoot = mvQuery.from(MetadataValue.class);
+            mvPredicates.add(criteriaBuilder.equal(
+                    mvRoot.get(MetadataValue_.D_SPACE_OBJECT), root.get(DSpaceObject_.ID)));
+
+            if (!predicate.getFields().isEmpty()) {
+                In<MetadataField> inFields = criteriaBuilder.in(mvRoot.get(MetadataValue_.METADATA_FIELD));
+                predicate.getFields().forEach(inFields::value);
+                mvPredicates.add(inFields);
+            }
+
+            JpaCriteriaBuilderKit<MetadataValue> jpaKit = new JpaCriteriaBuilderKit<>(criteriaBuilder, mvQuery, mvRoot);
+            mvPredicates.add(op.buildJpaPredicate(predicate.getValue(), regexClause, jpaKit));
+
+            mvQuery.select(mvRoot.get(MetadataValue_.D_SPACE_OBJECT))
+                    .where(mvPredicates.stream().toArray(Predicate[]::new));
+
+            if (op.getNegate()) {
+                predicates.add(criteriaBuilder.not(criteriaBuilder.exists(mvQuery)));
+            } else {
+                predicates.add(criteriaBuilder.exists(mvQuery));
+            }
+        }
+
+        log.debug(String.format("Running custom query with %d filters", queryPredicates.size()));
+        return predicates;
+    }
+
     @Override
     public Iterator<Item> findByAuthorityValue(Context context, MetadataField metadataField, String authority,
                                                boolean inArchive) throws SQLException {
@@ -197,22 +306,22 @@ public class ItemDAOImpl extends AbstractHibernateDSODAO<Item> implements ItemDA
     public Iterator<Item> findArchivedByCollectionExcludingOwning(Context context, Collection collection, Integer limit,
                                                                   Integer offset) throws SQLException {
         CriteriaBuilder criteriaBuilder = getCriteriaBuilder(context);
-        CriteriaQuery criteriaQuery = getCriteriaQuery(criteriaBuilder, Item.class);
+        CriteriaQuery<Item> criteriaQuery = getCriteriaQuery(criteriaBuilder, Item.class);
         Root<Item> itemRoot = criteriaQuery.from(Item.class);
         criteriaQuery.select(itemRoot);
         criteriaQuery.where(criteriaBuilder.and(
                 criteriaBuilder.notEqual(itemRoot.get(Item_.owningCollection), collection),
                 criteriaBuilder.isMember(collection, itemRoot.get(Item_.collections)),
                 criteriaBuilder.isTrue(itemRoot.get(Item_.inArchive))));
-        criteriaQuery.orderBy(criteriaBuilder.asc(itemRoot.get(Item_.id)));
+        criteriaQuery.orderBy(criteriaBuilder.asc(itemRoot.get(DSpaceObject_.id)));
-        criteriaQuery.groupBy(itemRoot.get(Item_.id));
+        criteriaQuery.groupBy(itemRoot.get(DSpaceObject_.id));
         return list(context, criteriaQuery, false, Item.class, limit, offset).iterator();
     }
 
     @Override
     public int countArchivedByCollectionExcludingOwning(Context context, Collection collection) throws SQLException {
         CriteriaBuilder criteriaBuilder = getCriteriaBuilder(context);
-        CriteriaQuery criteriaQuery = getCriteriaQuery(criteriaBuilder, Item.class);
+        CriteriaQuery<Item> criteriaQuery = getCriteriaQuery(criteriaBuilder, Item.class);
         Root<Item> itemRoot = criteriaQuery.from(Item.class);
         criteriaQuery.select(itemRoot);
         criteriaQuery.where(criteriaBuilder.and(

dspace-api/src/main/java/org/dspace/content/service/ItemService.java

@@ -26,6 +26,7 @@ import org.dspace.content.Item;
 import org.dspace.content.MetadataValue;
 import org.dspace.content.Thumbnail;
 import org.dspace.content.WorkspaceItem;
+import org.dspace.contentreport.QueryPredicate;
 import org.dspace.core.Context;
 import org.dspace.discovery.SearchServiceException;
 import org.dspace.eperson.EPerson;
@@ -41,7 +42,7 @@ import org.dspace.eperson.Group;
 public interface ItemService
         extends DSpaceObjectService<Item>, DSpaceObjectLegacySupportService<Item> {
 
-    public Thumbnail getThumbnail(Context context, Item item, boolean requireOriginal) throws SQLException;
+    Thumbnail getThumbnail(Context context, Item item, boolean requireOriginal) throws SQLException;
 
     /**
      * Create a new item, with a new internal ID. Authorization is done
@@ -53,7 +54,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public Item create(Context context, WorkspaceItem workspaceItem) throws SQLException, AuthorizeException;
+    Item create(Context context, WorkspaceItem workspaceItem) throws SQLException, AuthorizeException;
 
     /**
      * Create a new item, with a provided ID. Authorisation is done
@@ -66,7 +67,7 @@ public interface ItemService
      * @throws SQLException if database error
      * @throws AuthorizeException if authorization error
      */
-    public Item create(Context context, WorkspaceItem workspaceItem, UUID uuid) throws SQLException, AuthorizeException;
+    Item create(Context context, WorkspaceItem workspaceItem, UUID uuid) throws SQLException, AuthorizeException;
 
     /**
      * Create an empty template item for this collection. If one already exists,
@@ -80,7 +81,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public Item createTemplateItem(Context context, Collection collection) throws SQLException, AuthorizeException;
+    Item createTemplateItem(Context context, Collection collection) throws SQLException, AuthorizeException;
 
     /**
      * Get all the items in the archive. Only items with the "in archive" flag
@@ -90,7 +91,7 @@ public interface ItemService
      * @return an iterator over the items in the archive.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findAll(Context context) throws SQLException;
+    Iterator<Item> findAll(Context context) throws SQLException;
 
     /**
      * Get all the items in the archive. Only items with the "in archive" flag
@@ -102,7 +103,7 @@ public interface ItemService
      * @return an iterator over the items in the archive.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findAll(Context context, Integer limit, Integer offset) throws SQLException;
+    Iterator<Item> findAll(Context context, Integer limit, Integer offset) throws SQLException;
 
     /**
      * Get all "final" items in the archive, both archived ("in archive" flag) or
@@ -112,8 +113,7 @@ public interface ItemService
      * @return an iterator over the items in the archive.
      * @throws SQLException if database error
      */
-    @Deprecated
+    @Deprecated Iterator<Item> findAllUnfiltered(Context context) throws SQLException;
-    public Iterator<Item> findAllUnfiltered(Context context) throws SQLException;
 
     /**
      * Find all items that are:
@@ -126,7 +126,7 @@ public interface ItemService
      * @return iterator over all regular items.
      * @throws SQLException if database error.
      */
-    public Iterator<Item> findAllRegularItems(Context context) throws SQLException;
+    Iterator<Item> findAllRegularItems(Context context) throws SQLException;
 
     /**
      * Find all the items in the archive by a given submitter. The order is
@@ -137,7 +137,7 @@ public interface ItemService
      * @return an iterator over the items submitted by eperson
      * @throws SQLException if database error
      */
-    public Iterator<Item> findBySubmitter(Context context, EPerson eperson)
+    Iterator<Item> findBySubmitter(Context context, EPerson eperson)
         throws SQLException;
 
     /**
@@ -152,7 +152,7 @@ public interface ItemService
      * @return an iterator over the items submitted by eperson
      * @throws SQLException if database error
      */
-    public Iterator<Item> findBySubmitter(Context context, EPerson eperson, boolean retrieveAllItems)
+    Iterator<Item> findBySubmitter(Context context, EPerson eperson, boolean retrieveAllItems)
             throws SQLException;
 
     /**
@@ -164,7 +164,7 @@ public interface ItemService
      * @return an iterator over the items submitted by eperson
      * @throws SQLException if database error
      */
-    public Iterator<Item> findBySubmitterDateSorted(Context context, EPerson eperson, Integer limit)
+    Iterator<Item> findBySubmitterDateSorted(Context context, EPerson eperson, Integer limit)
         throws SQLException;
 
     /**
@@ -175,7 +175,7 @@ public interface ItemService
      * @return an iterator over the items in the collection.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findByCollection(Context context, Collection collection) throws SQLException;
+    Iterator<Item> findByCollection(Context context, Collection collection) throws SQLException;
 
     /**
      * Get all the archived items in this collection. The order is indeterminate.
@@ -187,7 +187,7 @@ public interface ItemService
      * @return an iterator over the items in the collection.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findByCollection(Context context, Collection collection, Integer limit, Integer offset)
+    Iterator<Item> findByCollection(Context context, Collection collection, Integer limit, Integer offset)
         throws SQLException;
 
     /**
@@ -200,7 +200,7 @@ public interface ItemService
      * @return an iterator over the items in the collection.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findByCollectionMapping(Context context, Collection collection, Integer limit, Integer offset)
+    Iterator<Item> findByCollectionMapping(Context context, Collection collection, Integer limit, Integer offset)
             throws SQLException;
 
     /**
@@ -211,7 +211,7 @@ public interface ItemService
      * @return an iterator over the items in the collection.
      * @throws SQLException if database error
      */
-    public int countByCollectionMapping(Context context, Collection collection) throws SQLException;
+    int countByCollectionMapping(Context context, Collection collection) throws SQLException;
 
     /**
      * Get all the items (including private and withdrawn) in this collection. The order is indeterminate.
@@ -223,7 +223,7 @@ public interface ItemService
      * @param offset offset value
      * @throws SQLException if database error
      */
-    public Iterator<Item> findAllByCollection(Context context, Collection collection, Integer limit, Integer offset)
+    Iterator<Item> findAllByCollection(Context context, Collection collection, Integer limit, Integer offset)
         throws SQLException;
 
     /**
@@ -234,7 +234,7 @@ public interface ItemService
      * @return an iterator over the items in the collection.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findInArchiveOrWithdrawnDiscoverableModifiedSince(Context context, Date since)
+    Iterator<Item> findInArchiveOrWithdrawnDiscoverableModifiedSince(Context context, Date since)
         throws SQLException;
 
     /**
@@ -244,7 +244,7 @@ public interface ItemService
      * @return an iterator over the items in the collection.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findInArchiveOrWithdrawnNonDiscoverableModifiedSince(Context context, Date since)
+    Iterator<Item> findInArchiveOrWithdrawnNonDiscoverableModifiedSince(Context context, Date since)
         throws SQLException;
 
     /**
@@ -255,7 +255,7 @@ public interface ItemService
      * @return an iterator over the items in the collection.
      * @throws SQLException if database error
      */
-    public Iterator<Item> findAllByCollection(Context context, Collection collection) throws SQLException;
+    Iterator<Item> findAllByCollection(Context context, Collection collection) throws SQLException;
 
     /**
      * See whether this Item is contained by a given Collection.
@@ -265,7 +265,7 @@ public interface ItemService
      * @return true if {@code collection} contains this Item.
      * @throws SQLException if database error
      */
-    public boolean isIn(Item item, Collection collection) throws SQLException;
+    boolean isIn(Item item, Collection collection) throws SQLException;
 
     /**
      * Get the communities this item is in. Returns an unordered array of the
@@ -277,7 +277,7 @@ public interface ItemService
      * @return the communities this item is in.
      * @throws SQLException if database error
      */
-    public List<Community> getCommunities(Context context, Item item) throws SQLException;
+    List<Community> getCommunities(Context context, Item item) throws SQLException;
 
 
     /**
@@ -288,7 +288,7 @@ public interface ItemService
      * @return the bundles in an unordered array
      * @throws SQLException if database error
      */
-    public List<Bundle> getBundles(Item item, String name) throws SQLException;
+    List<Bundle> getBundles(Item item, String name) throws SQLException;
 
     /**
      * Add an existing bundle to this item. This has immediate effect.
@@ -299,7 +299,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public void addBundle(Context context, Item item, Bundle bundle) throws SQLException, AuthorizeException;
+    void addBundle(Context context, Item item, Bundle bundle) throws SQLException, AuthorizeException;
 
     /**
      * Remove a bundle. This may result in the bundle being deleted, if the
@@ -312,7 +312,7 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public void removeBundle(Context context, Item item, Bundle bundle) throws SQLException, AuthorizeException,
+    void removeBundle(Context context, Item item, Bundle bundle) throws SQLException, AuthorizeException,
         IOException;
 
     /**
@@ -325,7 +325,7 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public void removeAllBundles(Context context, Item item) throws AuthorizeException, SQLException, IOException;
+    void removeAllBundles(Context context, Item item) throws AuthorizeException, SQLException, IOException;
 
     /**
      * Create a single bitstream in a new bundle. Provided as a convenience
@@ -340,7 +340,7 @@ public interface ItemService
      * @throws IOException        if IO error
      * @throws SQLException       if database error
      */
-    public Bitstream createSingleBitstream(Context context, InputStream is, Item item, String name)
+    Bitstream createSingleBitstream(Context context, InputStream is, Item item, String name)
         throws AuthorizeException, IOException, SQLException;
 
     /**
@@ -354,7 +354,7 @@ public interface ItemService
      * @throws IOException        if IO error
      * @throws SQLException       if database error
      */
-    public Bitstream createSingleBitstream(Context context, InputStream is, Item item)
+    Bitstream createSingleBitstream(Context context, InputStream is, Item item)
         throws AuthorizeException, IOException, SQLException;
 
     /**
@@ -367,7 +367,7 @@ public interface ItemService
      * @return non-internal bitstreams.
      * @throws SQLException if database error
      */
-    public List<Bitstream> getNonInternalBitstreams(Context context, Item item) throws SQLException;
+    List<Bitstream> getNonInternalBitstreams(Context context, Item item) throws SQLException;
 
     /**
      * Remove just the DSpace license from an item This is useful to update the
@@ -382,7 +382,7 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public void removeDSpaceLicense(Context context, Item item) throws SQLException, AuthorizeException,
+    void removeDSpaceLicense(Context context, Item item) throws SQLException, AuthorizeException,
         IOException;
 
     /**
@@ -394,7 +394,7 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public void removeLicenses(Context context, Item item) throws SQLException, AuthorizeException, IOException;
+    void removeLicenses(Context context, Item item) throws SQLException, AuthorizeException, IOException;
 
     /**
      * Withdraw the item from the archive. It is kept in place, and the content
@@ -405,7 +405,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public void withdraw(Context context, Item item) throws SQLException, AuthorizeException;
+    void withdraw(Context context, Item item) throws SQLException, AuthorizeException;
 
 
     /**
@@ -416,7 +416,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public void reinstate(Context context, Item item) throws SQLException, AuthorizeException;
+    void reinstate(Context context, Item item) throws SQLException, AuthorizeException;
 
     /**
      * Return true if this Collection 'owns' this item
@@ -425,7 +425,7 @@ public interface ItemService
      * @param collection Collection
      * @return true if this Collection owns this item
      */
-    public boolean isOwningCollection(Item item, Collection collection);
+    boolean isOwningCollection(Item item, Collection collection);
 
     /**
      * remove all of the policies for item and replace them with a new list of
@@ -439,7 +439,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public void replaceAllItemPolicies(Context context, Item item, List<ResourcePolicy> newpolicies)
+    void replaceAllItemPolicies(Context context, Item item, List<ResourcePolicy> newpolicies)
         throws SQLException,
         AuthorizeException;
 
@@ -455,7 +455,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public void replaceAllBitstreamPolicies(Context context, Item item, List<ResourcePolicy> newpolicies)
+    void replaceAllBitstreamPolicies(Context context, Item item, List<ResourcePolicy> newpolicies)
         throws SQLException, AuthorizeException;
 
 
@@ -469,7 +469,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public void removeGroupPolicies(Context context, Item item, Group group) throws SQLException, AuthorizeException;
+    void removeGroupPolicies(Context context, Item item, Group group) throws SQLException, AuthorizeException;
 
     /**
      * Remove all policies on an item and its contents, and replace them with
@@ -484,7 +484,7 @@ public interface ItemService
      *                            draconian, but default policies must be enforced.
      * @throws AuthorizeException if authorization error
      */
-    public void inheritCollectionDefaultPolicies(Context context, Item item, Collection collection)
+    void inheritCollectionDefaultPolicies(Context context, Item item, Collection collection)
         throws java.sql.SQLException, AuthorizeException;
 
     /**
@@ -503,7 +503,7 @@ public interface ItemService
      *                            draconian, but default policies must be enforced.
      * @throws AuthorizeException if authorization error
      */
-    public void inheritCollectionDefaultPolicies(Context context, Item item, Collection collection,
+    void inheritCollectionDefaultPolicies(Context context, Item item, Collection collection,
                                                  boolean overrideItemReadPolicies)
         throws java.sql.SQLException, AuthorizeException;
 
@@ -516,14 +516,14 @@ public interface ItemService
      * already applied to the bundle/bitstream. Collection's policies are inherited
      * if there are no other policies defined or if the append mode is defined by
      * the configuration via the core.authorization.installitem.inheritance-read.append-mode property
-     * 
+     *
      * @param context             DSpace context object
      * @param item                Item to adjust policies on
      * @param collection          Collection
      * @throws SQLException       If database error
      * @throws AuthorizeException If authorization error
      */
-    public void adjustBundleBitstreamPolicies(Context context, Item item, Collection collection)
+    void adjustBundleBitstreamPolicies(Context context, Item item, Collection collection)
         throws SQLException, AuthorizeException;
 
     /**
@@ -544,7 +544,7 @@ public interface ItemService
      * @throws SQLException       If database error
      * @throws AuthorizeException If authorization error
      */
-    public void adjustBundleBitstreamPolicies(Context context, Item item, Collection collection,
+    void adjustBundleBitstreamPolicies(Context context, Item item, Collection collection,
                                               boolean replaceReadRPWithCollectionRP)
         throws SQLException, AuthorizeException;
 
@@ -565,7 +565,7 @@ public interface ItemService
      * @throws SQLException       If database error
      * @throws AuthorizeException If authorization error
      */
-    public void adjustBitstreamPolicies(Context context, Item item, Collection collection, Bitstream bitstream)
+    void adjustBitstreamPolicies(Context context, Item item, Collection collection, Bitstream bitstream)
         throws SQLException, AuthorizeException;
 
     /**
@@ -587,7 +587,7 @@ public interface ItemService
      * @throws SQLException       If database error
      * @throws AuthorizeException If authorization error
      */
-    public void adjustBitstreamPolicies(Context context, Item item, Collection collection, Bitstream bitstream,
+    void adjustBitstreamPolicies(Context context, Item item, Collection collection, Bitstream bitstream,
                                         boolean replaceReadRPWithCollectionRP)
         throws SQLException, AuthorizeException;
 
@@ -599,14 +599,14 @@ public interface ItemService
      * inherited as appropriate. Collection's policies are inherited if there are no
      * other policies defined or if the append mode is defined by the configuration
      * via the core.authorization.installitem.inheritance-read.append-mode property
-     * 
+     *
      * @param context              DSpace context object
      * @param item                 Item to adjust policies on
      * @param collection           Collection
      * @throws SQLException        If database error
      * @throws AuthorizeException  If authorization error
      */
-    public void adjustItemPolicies(Context context, Item item, Collection collection)
+    void adjustItemPolicies(Context context, Item item, Collection collection)
         throws SQLException, AuthorizeException;
 
     /**
@@ -625,7 +625,7 @@ public interface ItemService
      * @throws SQLException        If database error
      * @throws AuthorizeException  If authorization error
      */
-    public void adjustItemPolicies(Context context, Item item, Collection collection,
+    void adjustItemPolicies(Context context, Item item, Collection collection,
                                    boolean replaceReadRPWithCollectionRP)
         throws SQLException, AuthorizeException;
 
@@ -640,7 +640,7 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public void move(Context context, Item item, Collection from, Collection to)
+    void move(Context context, Item item, Collection from, Collection to)
         throws SQLException, AuthorizeException, IOException;
 
     /**
@@ -655,7 +655,7 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public void move(Context context, Item item, Collection from, Collection to, boolean inheritDefaultPolicies)
+    void move(Context context, Item item, Collection from, Collection to, boolean inheritDefaultPolicies)
         throws SQLException, AuthorizeException, IOException;
 
     /**
@@ -666,7 +666,7 @@ public interface ItemService
      * bitstreams inside
      * @throws SQLException if database error
      */
-    public boolean hasUploadedFiles(Item item) throws SQLException;
+    boolean hasUploadedFiles(Item item) throws SQLException;
 
     /**
      * Get the collections this item is not in.
@@ -676,7 +676,7 @@ public interface ItemService
      * @return the collections this item is not in, if any.
      * @throws SQLException if database error
      */
-    public List<Collection> getCollectionsNotLinked(Context context, Item item) throws SQLException;
+    List<Collection> getCollectionsNotLinked(Context context, Item item) throws SQLException;
 
     /**
      * return TRUE if context's user can edit item, false otherwise
@@ -686,7 +686,7 @@ public interface ItemService
      * @return boolean true = current user can edit item
      * @throws SQLException if database error
      */
-    public boolean canEdit(Context context, Item item) throws java.sql.SQLException;
+    boolean canEdit(Context context, Item item) throws java.sql.SQLException;
 
     /**
      * return TRUE if context's user can create new version of the item, false
@@ -697,7 +697,7 @@ public interface ItemService
      * @return boolean true = current user can create new version of the item
      * @throws SQLException if database error
      */
-    public boolean canCreateNewVersion(Context context, Item item) throws SQLException;
+    boolean canCreateNewVersion(Context context, Item item) throws SQLException;
 
     /**
      * Returns an iterator of in archive items possessing the passed metadata field, or only
@@ -712,7 +712,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public Iterator<Item> findArchivedByMetadataField(Context context, String schema,
+    Iterator<Item> findArchivedByMetadataField(Context context, String schema,
                                                       String element, String qualifier,
                                                       String value) throws SQLException, AuthorizeException;
 
@@ -727,7 +727,7 @@ public interface ItemService
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public Iterator<Item> findArchivedByMetadataField(Context context, String metadataField, String value)
+    Iterator<Item> findArchivedByMetadataField(Context context, String metadataField, String value)
             throws SQLException, AuthorizeException;
 
     /**
@@ -744,10 +744,42 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public Iterator<Item> findByMetadataField(Context context,
+    Iterator<Item> findByMetadataField(Context context,
                                               String schema, String element, String qualifier, String value)
         throws SQLException, AuthorizeException, IOException;
 
+    /**
+     * Returns a list of items that match the given predicates, within the
+     * specified collections, if any. This querying method is used by the
+     * Filtered Items report functionality.
+     * @param context DSpace context object
+     * @param queryPredicates metadata field predicates
+     * @param collectionUuids UUIDs of the collections to search
+     * @param offset position in the list to start returning items
+     * @param limit maximum number of items to return
+     * @return a list of matching items in the specified collections,
+     * or in any collection if no collection UUIDs are provided
+     * @throws SQLException if a database error occurs
+     */
+    List<Item> findByMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids, long offset, int limit)
+            throws SQLException;
+
+    /**
+     * Returns the total number of items that match the given predicates, within the
+     * specified collections, if any. This querying method is used for pagination by the
+     * Filtered Items report functionality.
+     * @param context DSpace context object
+     * @param queryPredicates metadata field predicates
+     * @param collectionUuids UUIDs of the collections to search
+     * @return the total number of matching items in the specified collections,
+     * or in any collection if no collection UUIDs are provided
+     * @throws SQLException if a database error occurs
+     */
+    long countForMetadataQuery(Context context, List<QueryPredicate> queryPredicates,
+            List<UUID> collectionUuids)
+            throws SQLException;
+
     /**
      * Find all the items in the archive with a given authority key value
      * in the indicated metadata field.
@@ -762,12 +794,12 @@ public interface ItemService
      * @throws AuthorizeException if authorization error
      * @throws IOException        if IO error
      */
-    public Iterator<Item> findByAuthorityValue(Context context,
+    Iterator<Item> findByAuthorityValue(Context context,
                                                String schema, String element, String qualifier, String value)
         throws SQLException, AuthorizeException;
 
 
-    public Iterator<Item> findByMetadataFieldAuthority(Context context, String mdString, String authority)
+    Iterator<Item> findByMetadataFieldAuthority(Context context, String mdString, String authority)
         throws SQLException, AuthorizeException;
 
     /**
@@ -779,7 +811,7 @@ public interface ItemService
      * @param item    item
      * @return true or false
      */
-    public boolean isItemListedForUser(Context context, Item item);
+    boolean isItemListedForUser(Context context, Item item);
 
     /**
      * counts items in the given collection
@@ -789,7 +821,7 @@ public interface ItemService
      * @return total items
      * @throws SQLException if database error
      */
-    public int countItems(Context context, Collection collection) throws SQLException;
+    int countItems(Context context, Collection collection) throws SQLException;
 
     /**
      * counts all items in the given collection including withdrawn items
@@ -799,7 +831,7 @@ public interface ItemService
      * @return total items
      * @throws SQLException if database error
      */
-    public int countAllItems(Context context, Collection collection) throws SQLException;
+    int countAllItems(Context context, Collection collection) throws SQLException;
 
     /**
      * Find all Items modified since a Date.
@@ -809,7 +841,7 @@ public interface ItemService
      * @return iterator over items
      * @throws SQLException if database error
      */
-    public Iterator<Item> findByLastModifiedSince(Context context, Date last)
+    Iterator<Item> findByLastModifiedSince(Context context, Date last)
         throws SQLException;
 
     /**
@@ -820,7 +852,7 @@ public interface ItemService
      * @return total items
      * @throws SQLException if database error
      */
-    public int countItems(Context context, Community community) throws SQLException;
+    int countItems(Context context, Community community) throws SQLException;
 
     /**
      * counts all items in the given community including withdrawn
@@ -830,7 +862,7 @@ public interface ItemService
      * @return total items
      * @throws SQLException if database error
      */
-    public int countAllItems(Context context, Community community) throws SQLException;
+    int countAllItems(Context context, Community community) throws SQLException;
 
     /**
      * counts all items
@@ -877,7 +909,7 @@ public interface ItemService
       * @throws SQLException
       * @throws SearchServiceException
       */
-    public List<Item> findItemsWithEdit(Context context, int offset, int limit)
+    List<Item> findItemsWithEdit(Context context, int offset, int limit)
         throws SQLException, SearchServiceException;
 
     /**
@@ -887,7 +919,7 @@ public interface ItemService
     * @throws SQLException
     * @throws SearchServiceException
     */
-    public int countItemsWithEdit(Context context) throws SQLException, SearchServiceException;
+    int countItemsWithEdit(Context context) throws SQLException, SearchServiceException;
 
     /**
      * Check if the supplied item is an inprogress submission
@@ -947,7 +979,7 @@ public interface ItemService
      *                     relationships.
      * @return metadata fields that match the parameters
      */
-    public List<MetadataValue> getMetadata(Item item, String schema, String element, String qualifier,
+    List<MetadataValue> getMetadata(Item item, String schema, String element, String qualifier,
                                            String lang, boolean enableVirtualMetadata);
 
     /**
@@ -955,7 +987,7 @@ public interface ItemService
      * @param item the item.
      * @return the label of the entity type, taken from the item metadata, or null if not found.
      */
-    public String getEntityTypeLabel(Item item);
+    String getEntityTypeLabel(Item item);
 
     /**
      * Retrieve the entity type of the given item.
@@ -963,6 +995,6 @@ public interface ItemService
      * @param item the item.
      * @return the entity type of the given item, or null if not found.
      */
-    public EntityType getEntityType(Context context, Item item) throws SQLException;
+    EntityType getEntityType(Context context, Item item) throws SQLException;
 
 }

dspace-api/src/main/java/org/dspace/contentreport/ContentReportServiceImpl.java

@@ -0,0 +1,190 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Set;
+import java.util.UUID;
+
+import org.apache.logging.log4j.Logger;
+import org.dspace.content.Collection;
+import org.dspace.content.Community;
+import org.dspace.content.Item;
+import org.dspace.content.MetadataField;
+import org.dspace.content.service.CollectionService;
+import org.dspace.content.service.ItemService;
+import org.dspace.content.service.MetadataFieldService;
+import org.dspace.contentreport.service.ContentReportService;
+import org.dspace.core.Context;
+import org.dspace.services.ConfigurationService;
+import org.springframework.beans.factory.annotation.Autowired;
+
+public class ContentReportServiceImpl implements ContentReportService {
+
+    private static final Logger log = org.apache.logging.log4j.LogManager
+            .getLogger(ContentReportServiceImpl.class);
+
+    @Autowired
+    protected ConfigurationService configurationService;
+    @Autowired
+    private CollectionService collectionService;
+    @Autowired
+    private ItemService itemService;
+    @Autowired
+    private MetadataFieldService metadataFieldService;
+
+    /**
+     * Returns <code>true<</code> if Content Reports are enabled.
+     * @return <code>true<</code> if Content Reports are enabled
+     */
+    @Override
+    public boolean getEnabled() {
+        return configurationService.getBooleanProperty("contentreport.enable");
+    }
+
+    /**
+     * Retrieves item statistics per collection according to a set of Boolean filters.
+     * @param context DSpace context
+     * @param filters Set of filters
+     * @return a list of collections with the requested statistics for each of them
+     */
+    @Override
+    public List<FilteredCollection> findFilteredCollections(Context context, java.util.Collection<Filter> filters) {
+        List<FilteredCollection> colls = new ArrayList<>();
+        try {
+            List<Collection> collections = collectionService.findAll(context);
+            for (Collection collection : collections) {
+                FilteredCollection coll = new FilteredCollection();
+                coll.setHandle(collection.getHandle());
+                coll.setLabel(collection.getName());
+                Community community = collection.getCommunities().stream()
+                        .findFirst()
+                        .orElse(null);
+                if (community != null) {
+                    coll.setCommunityLabel(community.getName());
+                    coll.setCommunityHandle(community.getHandle());
+                }
+                colls.add(coll);
+
+                Iterator<Item> items = itemService.findAllByCollection(context, collection);
+                int nbTotalItems = 0;
+                while (items.hasNext()) {
+                    Item item = items.next();
+                    nbTotalItems++;
+                    boolean matchesAllFilters = true;
+                    for (Filter filter : filters) {
+                        if (filter.testItem(context, item)) {
+                            coll.addValue(filter, 1);
+                        } else {
+                            // This ensures the requested filter is present in the collection record
+                            // even when there are no matching items.
+                            coll.addValue(filter, 0);
+                            matchesAllFilters = false;
+                        }
+                    }
+                    if (matchesAllFilters) {
+                        coll.addAllFiltersValue(1);
+                    }
+                }
+                coll.setTotalItems(nbTotalItems);
+                coll.seal();
+            }
+        } catch (SQLException e) {
+            log.error("SQLException trying to receive filtered collections statistics", e);
+        }
+        return colls;
+    }
+
+    /**
+     * Retrieves a list of items according to a set of criteria.
+     * @param context DSpace context
+     * @param query structured query to find items against
+     * @return a list of items filtered according to the provided query
+     */
+    @Override
+    public FilteredItems findFilteredItems(Context context, FilteredItemsQuery query) {
+        FilteredItems report = new FilteredItems();
+
+        List<QueryPredicate> predicates = query.getQueryPredicates();
+        List<UUID> collectionUuids = getUuidsFromStrings(query.getCollections());
+        Set<Filter> filters = query.getFilters();
+
+        try {
+            List<Item> items = itemService.findByMetadataQuery(context, predicates, collectionUuids,
+                    query.getOffset(), query.getPageLimit());
+            items.stream()
+                    .filter(item -> filters.stream().allMatch(f -> f.testItem(context, item)))
+                    .forEach(report::addItem);
+        } catch (SQLException e) {
+            log.error(e.getMessage(), e);
+        }
+        try {
+            long count = itemService.countForMetadataQuery(context, predicates, collectionUuids);
+            report.setItemCount(count);
+        } catch (SQLException e) {
+            log.error(e.getMessage(), e);
+        }
+
+        return report;
+    }
+
+    /**
+     * Converts a metadata field name to a list of {@link MetadataField} instances
+     * (one if no wildcards are used, possibly more otherwise).
+     * @param context DSpace context
+     * @param metadataField field to search for
+     * @return a corresponding list of {@link MetadataField} entries
+     */
+    @Override
+    public List<MetadataField> getMetadataFields(org.dspace.core.Context context, String metadataField)
+            throws SQLException {
+        List<MetadataField> fields = new ArrayList<>();
+        if ("*".equals(metadataField)) {
+            return fields;
+        }
+        String schema = "";
+        String element = "";
+        String qualifier = null;
+        String[] parts = metadataField.split("\\.");
+        if (parts.length > 0) {
+            schema = parts[0];
+        }
+        if (parts.length > 1) {
+            element = parts[1];
+        }
+        if (parts.length > 2) {
+            qualifier = parts[2];
+        }
+
+        if (Item.ANY.equals(qualifier)) {
+            fields.addAll(metadataFieldService.findFieldsByElementNameUnqualified(context, schema, element));
+        } else {
+            MetadataField mf = metadataFieldService.findByElement(context, schema, element, qualifier);
+            if (mf != null) {
+                fields.add(mf);
+            }
+        }
+        return fields;
+    }
+
+    private static List<UUID> getUuidsFromStrings(List<String> collSel) {
+        List<UUID> uuids = new ArrayList<>();
+        for (String s: collSel) {
+            try {
+                uuids.add(UUID.fromString(s));
+            } catch (IllegalArgumentException e) {
+                log.warn("Invalid collection UUID: " + s);
+            }
+        }
+        return uuids;
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/Filter.java

@@ -0,0 +1,399 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.sql.SQLException;
+import java.util.Arrays;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.Set;
+import java.util.function.BiPredicate;
+import java.util.stream.Collectors;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.dspace.authorize.factory.AuthorizeServiceFactory;
+import org.dspace.authorize.service.AuthorizeService;
+import org.dspace.content.Bundle;
+import org.dspace.content.Item;
+import org.dspace.contentreport.ItemFilterUtil.BundleName;
+import org.dspace.core.Context;
+import org.dspace.services.factory.DSpaceServicesFactory;
+
+/**
+ * Available filters for the Filtered Collections and Filtered Items reports.
+ * In this enum, each item corresponds to a separate property, not values of
+ * a single property, hence the @JsonProperty applied to each of them.
+ * For each item, the annotation value is read through reflection and copied into
+ * the id property, which eliminates repetitions, hence reducing the risk or errors.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public enum Filter {
+
+    @JsonProperty("is_item")
+    IS_ITEM(FilterCategory.PROPERTY, (context, item) -> true),
+    @JsonProperty("is_withdrawn")
+    IS_WITHDRAWN(FilterCategory.PROPERTY, (context, item) -> item.isWithdrawn()),
+    @JsonProperty("is_not_withdrawn")
+    IS_NOT_WITHDRAWN(FilterCategory.PROPERTY, (context, item) -> !item.isWithdrawn()),
+    @JsonProperty("is_discoverable")
+    IS_DISCOVERABLE(FilterCategory.PROPERTY, (context, item) -> item.isDiscoverable()),
+    @JsonProperty("is_not_discoverable")
+    IS_NOT_DISCOVERABLE(FilterCategory.PROPERTY, (context, item) -> !item.isDiscoverable()),
+
+    /**
+     * Matches items having multiple original bitstreams.
+     */
+    @JsonProperty("has_multiple_originals")
+    HAS_MULTIPLE_ORIGINALS(FilterCategory.BITSTREAM, (context, item) ->
+        ItemFilterUtil.countOriginalBitstream(item) > 1),
+    /**
+     * Matches items having no original bitstreams.
+     */
+    @JsonProperty("has_no_originals")
+    HAS_NO_ORIGINALS(FilterCategory.BITSTREAM, (context, item) -> ItemFilterUtil.countOriginalBitstream(item) == 0),
+    /**
+     * Matches items having exactly one original bitstream.
+     */
+    @JsonProperty("has_one_original")
+    HAS_ONE_ORIGINAL(FilterCategory.BITSTREAM, (context, item) -> ItemFilterUtil.countOriginalBitstream(item) == 1),
+
+    /**
+     * Matches items having bitstreams with a MIME type that matches one defined in the "rest.report-mime-document"
+     * configuration property.
+     */
+    @JsonProperty("has_doc_original")
+    HAS_DOC_ORIGINAL(FilterCategory.BITSTREAM_MIME, (context, item) ->
+        ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.getDocumentMimeTypes()) > 0),
+    /**
+     * Matches items having bitstreams with a MIME type starting with "image" (e.g., image/jpeg, image/png).
+     */
+    @JsonProperty("has_image_original")
+    HAS_IMAGE_ORIGINAL(FilterCategory.BITSTREAM_MIME, (context, item) ->
+        ItemFilterUtil.countOriginalBitstreamMimeStartsWith(context, item, "image") > 0),
+    /**
+     * Matches items having bitstreams with a MIME type other than document (cf. HAS_DOCUMENT above) or image
+     * (cf. HAS_IMAGE_ORIGINAL above).
+     */
+    @JsonProperty("has_unsupp_type")
+    HAS_UNSUPPORTED_TYPE(FilterCategory.BITSTREAM_MIME, (context, item) -> {
+        int bitCount = ItemFilterUtil.countOriginalBitstream(item);
+        if (bitCount == 0) {
+            return false;
+        }
+        int docCount = ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.getDocumentMimeTypes());
+        int imgCount = ItemFilterUtil.countOriginalBitstreamMimeStartsWith(context, item, "image");
+        return (bitCount - docCount - imgCount) > 0;
+    }),
+    /**
+     * Matches items having bitstreams of multiple types (document, image, other).
+     */
+    @JsonProperty("has_mixed_original")
+    HAS_MIXED_ORIGINAL(FilterCategory.BITSTREAM_MIME, (context, item) -> {
+        int countBit = ItemFilterUtil.countOriginalBitstream(item);
+        if (countBit <= 1) {
+            return false;
+        }
+        int countDoc = ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.getDocumentMimeTypes());
+        if (countDoc > 0) {
+            return countDoc != countBit;
+        }
+        int countImg = ItemFilterUtil.countOriginalBitstreamMimeStartsWith(context, item, "image");
+        if (countImg > 0) {
+            return countImg != countBit;
+        }
+        return false;
+    }),
+    @JsonProperty("has_pdf_original")
+    HAS_PDF_ORIGINAL(FilterCategory.BITSTREAM_MIME, (context, item) ->
+        ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.MIMES_PDF) > 0),
+    @JsonProperty("has_jpg_original")
+    HAS_JPEG_ORIGINAL(FilterCategory.BITSTREAM_MIME, (context, item) ->
+        ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.MIMES_JPG) > 0),
+    /**
+     * Matches items having at least one PDF of size less than 20 kb (configurable in rest.cfg).
+     */
+    @JsonProperty("has_small_pdf")
+    HAS_SMALL_PDF(FilterCategory.BITSTREAM_MIME, (context, item) ->
+        ItemFilterUtil.countBitstreamSmallerThanMinSize(
+                context, BundleName.ORIGINAL, item, ItemFilterUtil.MIMES_PDF, "rest.report-pdf-min-size") > 0),
+    /**
+     * Matches items having at least one PDF of size more than 25 Mb (configurable in rest.cfg).
+     */
+    @JsonProperty("has_large_pdf")
+    HAS_LARGE_PDF(FilterCategory.BITSTREAM_MIME, (context, item) ->
+        ItemFilterUtil.countBitstreamLargerThanMaxSize(
+                context, BundleName.ORIGINAL,  item, ItemFilterUtil.MIMES_PDF, "rest.report-pdf-max-size") > 0),
+    /**
+     * Matches items having at least one non-text bitstream.
+     */
+    @JsonProperty("has_doc_without_text")
+    HAS_DOC_WITHOUT_TEXT(FilterCategory.BITSTREAM_MIME, (context, item) -> {
+        int countDoc = ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.getDocumentMimeTypes());
+        if (countDoc == 0) {
+            return false;
+        }
+        int countText = ItemFilterUtil.countBitstream(BundleName.TEXT, item);
+        return countDoc > countText;
+    }),
+
+    /**
+     * Matches items having at least one image, but all of supported types.
+     */
+    @JsonProperty("has_only_supp_image_type")
+    HAS_ONLY_SUPPORTED_IMAGE_TYPE(FilterCategory.MIME, (context, item) -> {
+        int imageCount = ItemFilterUtil.countOriginalBitstreamMimeStartsWith(context, item, "image/");
+        if (imageCount == 0) {
+            return false;
+        }
+        int suppImageCount = ItemFilterUtil.countOriginalBitstreamMime(
+                context, item, ItemFilterUtil.getSupportedImageMimeTypes());
+        return (imageCount == suppImageCount);
+    }),
+    /**
+     * Matches items having at least one image of an unsupported type.
+     */
+    @JsonProperty("has_unsupp_image_type")
+    HAS_UNSUPPORTED_IMAGE_TYPE(FilterCategory.MIME, (context, item) -> {
+        int imageCount = ItemFilterUtil.countOriginalBitstreamMimeStartsWith(context, item, "image/");
+        if (imageCount == 0) {
+            return false;
+        }
+        int suppImageCount = ItemFilterUtil.countOriginalBitstreamMime(
+                context, item, ItemFilterUtil.getSupportedImageMimeTypes());
+        return (imageCount - suppImageCount) > 0;
+    }),
+    /**
+     * Matches items having at least one document, but all of supported types.
+     */
+    @JsonProperty("has_only_supp_doc_type")
+    HAS_ONLY_SUPPORTED_DOC_TYPE(FilterCategory.MIME, (context, item) -> {
+        int docCount = ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.getDocumentMimeTypes());
+        if (docCount == 0) {
+            return false;
+        }
+        int suppDocCount = ItemFilterUtil.countOriginalBitstreamMime(
+                context, item, ItemFilterUtil.getSupportedDocumentMimeTypes());
+        return docCount == suppDocCount;
+    }),
+    /**
+     * Matches items having at least one document of an unsupported type.
+     */
+    @JsonProperty("has_unsupp_doc_type")
+    HAS_UNSUPPORTED_DOC_TYPE(FilterCategory.MIME, (context, item) -> {
+        int docCount = ItemFilterUtil.countOriginalBitstreamMime(context, item, ItemFilterUtil.getDocumentMimeTypes());
+        if (docCount == 0) {
+            return false;
+        }
+        int suppDocCount = ItemFilterUtil.countOriginalBitstreamMime(
+                context, item, ItemFilterUtil.getSupportedDocumentMimeTypes());
+        return (docCount - suppDocCount) > 0;
+    }),
+
+    /**
+     * Matches items having at least one unsupported bundle.
+     */
+    @JsonProperty("has_unsupported_bundle")
+    HAS_UNSUPPORTED_BUNDLE(FilterCategory.BUNDLE, (context, item) -> {
+        String[] bundleList = DSpaceServicesFactory.getInstance().getConfigurationService()
+                .getArrayProperty("rest.report-supp-bundles");
+        return ItemFilterUtil.hasUnsupportedBundle(item, bundleList);
+    }),
+    /**
+     * Matches items having at least one thumbnail of size less than 400 bytes (configurable in rest.cfg).
+     */
+    @JsonProperty("has_small_thumbnail")
+    HAS_SMALL_THUMBNAIL(FilterCategory.BUNDLE, (context, item) ->
+        ItemFilterUtil.countBitstreamSmallerThanMinSize(
+                context, BundleName.THUMBNAIL, item, ItemFilterUtil.MIMES_JPG, "rest.report-thumbnail-min-size") > 0),
+    /**
+     * Matches items having at least one original without a thumbnail.
+     */
+    @JsonProperty("has_original_without_thumbnail")
+    HAS_ORIGINAL_WITHOUT_THUMBNAIL(FilterCategory.BUNDLE, (context, item) -> {
+        int countBit = ItemFilterUtil.countOriginalBitstream(item);
+        if (countBit == 0) {
+            return false;
+        }
+        int countThumb = ItemFilterUtil.countBitstream(BundleName.THUMBNAIL, item);
+        return countBit > countThumb;
+    }),
+    /**
+     * Matches items having at least one non-JPEG thumbnail.
+     */
+    @JsonProperty("has_invalid_thumbnail_name")
+    HAS_INVALID_THUMBNAIL_NAME(FilterCategory.BUNDLE, (context, item) -> {
+        List<String> originalNames = ItemFilterUtil.getBitstreamNames(BundleName.ORIGINAL, item);
+        List<String> thumbNames = ItemFilterUtil.getBitstreamNames(BundleName.THUMBNAIL, item);
+        if (thumbNames.size() != originalNames.size()) {
+            return false;
+        }
+        return originalNames.stream()
+                .anyMatch(name -> !thumbNames.contains(name + ".jpg") && !thumbNames.contains(name + ".jpeg"));
+    }),
+    /**
+     * Matches items having at least one non-generated thumbnail.
+     */
+    @JsonProperty("has_non_generated_thumb")
+    HAS_NON_GENERATED_THUMBNAIL(FilterCategory.BUNDLE, (context, item) -> {
+        String[] generatedThumbDesc = DSpaceServicesFactory.getInstance().getConfigurationService()
+                .getArrayProperty("rest.report-gen-thumbnail-desc");
+        int countThumb = ItemFilterUtil.countBitstream(BundleName.THUMBNAIL, item);
+        if (countThumb == 0) {
+            return false;
+        }
+        int countGen = ItemFilterUtil.countBitstreamByDesc(BundleName.THUMBNAIL, item, generatedThumbDesc);
+        return (countThumb > countGen);
+    }),
+    /**
+     * Matches items having no licence-typed bitstreams.
+     */
+    @JsonProperty("no_license")
+    NO_LICENSE(FilterCategory.BUNDLE, (context, item) ->
+        ItemFilterUtil.countBitstream(BundleName.LICENSE, item) == 0),
+    /**
+     * Matches items having licence documentation (a licence bitstream named other than license.txt).
+     */
+    @JsonProperty("has_license_documentation")
+    HAS_LICENSE_DOCUMENTATION(FilterCategory.BUNDLE, (context, item) -> {
+        List<String> names = ItemFilterUtil.getBitstreamNames(BundleName.LICENSE, item);
+        return names.stream()
+                .anyMatch(name -> !name.equals("license.txt"));
+    }),
+
+    /**
+     * Matches items having at least one original with restricted access.
+     */
+    @JsonProperty("has_restricted_original")
+    HAS_RESTRICTED_ORIGINAL(FilterCategory.PERMISSION, (context, item) -> {
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(BundleName.ORIGINAL.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .anyMatch(bit -> {
+                    try {
+                        if (!getAuthorizeService()
+                                .authorizeActionBoolean(getAnonymousContext(), bit, org.dspace.core.Constants.READ)) {
+                            return true;
+                        }
+                    } catch (SQLException e) {
+                        getLog().warn("SQL Exception testing original bitstream access " + e.getMessage(), e);
+                    }
+                    return false;
+                });
+    }),
+    /**
+     * Matches items having at least one thumbnail with restricted access.
+     */
+    @JsonProperty("has_restricted_thumbnail")
+    HAS_RESTRICTED_THUMBNAIL(FilterCategory.PERMISSION, (context, item) -> {
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(BundleName.THUMBNAIL.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .anyMatch(bit -> {
+                    try {
+                        if (!getAuthorizeService()
+                                .authorizeActionBoolean(getAnonymousContext(), bit, org.dspace.core.Constants.READ)) {
+                            return true;
+                        }
+                    } catch (SQLException e) {
+                        getLog().warn("SQL Exception testing thumbnail bitstream access " + e.getMessage(), e);
+                    }
+                    return false;
+                });
+    }),
+    /**
+     * Matches items having metadata with restricted access.
+     */
+    @JsonProperty("has_restricted_metadata")
+    HAS_RESTRICTED_METADATA(FilterCategory.PERMISSION, (context, item) -> {
+        try {
+            return !getAuthorizeService()
+                    .authorizeActionBoolean(getAnonymousContext(), item, org.dspace.core.Constants.READ);
+        } catch (SQLException e) {
+            getLog().warn("SQL Exception testing item metadata access " + e.getMessage(), e);
+            return false;
+        }
+    });
+
+    private static final Logger log = LogManager.getLogger();
+    private static AuthorizeService authorizeService;
+    private static Context anonymousContext;
+
+    private String id;
+    private FilterCategory category;
+    private BiPredicate<Context, Item> itemTester;
+
+    Filter(FilterCategory category, BiPredicate<Context, Item> itemTester) {
+        try {
+            JsonProperty jp = getClass().getField(name()).getAnnotation(JsonProperty.class);
+            id = Optional.ofNullable(jp).map(JsonProperty::value).orElse(name());
+        } catch (Exception e) {
+            id = name();
+        }
+        this.category = category;
+        this.itemTester = itemTester;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public FilterCategory getCategory() {
+        return category;
+    }
+
+    public boolean testItem(Context context, Item item) {
+        return itemTester.test(context, item);
+    }
+
+    private static Logger getLog() {
+        return log;
+    }
+
+    private static AuthorizeService getAuthorizeService() {
+        if (authorizeService == null) {
+            authorizeService = AuthorizeServiceFactory.getInstance().getAuthorizeService();
+        }
+        return authorizeService;
+    }
+
+    private static Context getAnonymousContext() {
+        if (anonymousContext == null) {
+            anonymousContext = new Context();
+        }
+        return anonymousContext;
+    }
+
+    @JsonCreator
+    public static Filter get(String id) {
+        return Arrays.stream(values())
+                .filter(item -> Objects.equals(item.id, id))
+                .findFirst()
+                .orElse(null);
+    }
+
+    public static Set<Filter> getFilters(String filters) {
+        String[] ids = Optional.ofNullable(filters).orElse("").split("[^a-z_]+");
+        Set<Filter> set = Arrays.stream(ids)
+                .map(Filter::get)
+                .filter(f -> f != null)
+                .collect(Collectors.toCollection(() -> EnumSet.noneOf(Filter.class)));
+        if (set == null) {
+            set = EnumSet.noneOf(Filter.class);
+        }
+        return set;
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/FilterCategory.java

@@ -0,0 +1,50 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * Identifies the category/section of filters defined in the {@link Filter} enum.
+ * This enum will be used when/if the structured filter definitions are returned to
+ * the Angular layer through a REST endpoint.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public enum FilterCategory {
+
+    PROPERTY("property"),
+    BITSTREAM("bitstream"),
+    BITSTREAM_MIME("bitstream_mime"),
+    MIME("mime"),
+    BUNDLE("bundle"),
+    PERMISSION("permission");
+
+    private String id;
+    private List<Filter> filters;
+
+    FilterCategory(String id) {
+        this.id = id;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public List<Filter> getFilters() {
+        if (filters == null) {
+            filters = Arrays.stream(Filter.values())
+                    .filter(f -> f.getCategory() == this)
+                    .collect(Collectors.toUnmodifiableList());
+        }
+        return filters;
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/FilteredCollection.java

@@ -0,0 +1,219 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.io.Serializable;
+import java.util.EnumMap;
+import java.util.Map;
+import java.util.Optional;
+
+/**
+ * This class represents an entry in the Filtered Collections report.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredCollection implements Cloneable, Serializable {
+
+    private static final long serialVersionUID = -231735620268582719L;
+
+    /** Name of the collection */
+    private String label;
+    /** Handle of the collection, used to make it clickable from the generated report */
+    private String handle;
+    /** Name of the owning community */
+    private String communityLabel;
+    /** Handle of the owning community, used to make it clickable from the generated report */
+    private String communityHandle;
+    /** Total number of items in the collection */
+    private int totalItems;
+    /** Number of filtered items per requested filter in the collection */
+    private Map<Filter, Integer> values = new EnumMap<>(Filter.class);
+    /** Number of items in the collection that match all requested filters */
+    private int allFiltersValue;
+    /**
+     * Indicates whether this object is protected against further changes.
+     * This is used in computing summary data in the parent FilteredCollectionsRest class.
+     */
+    private boolean sealed;
+
+    /**
+     * Shortcut method that builds a FilteredCollectionRest instance
+     * from its building blocks.
+     * @param label Name of the collection
+     * @param handle Handle of the collection
+     * @param communityLabel Name of the owning community
+     * @param communityHandle Handle of the owning community
+     * @param totalItems Total number of items in the collection
+     * @param allFiltersValue Number of items in the collection that match all requested filters
+     * @param values Number of filtered items per requested filter in the collection
+     * @param doSeal true if the collection must be sealed immediately
+     * @return a FilteredCollectionRest instance built from the provided parameters
+     */
+    public static FilteredCollection of(String label, String handle,
+            String communityLabel, String communityHandle,
+            int totalItems, int allFiltersValue, Map<Filter, Integer> values, boolean doSeal) {
+        var coll = new FilteredCollection();
+        coll.label = label;
+        coll.handle = handle;
+        coll.communityLabel = communityLabel;
+        coll.communityHandle = communityHandle;
+        coll.totalItems = totalItems;
+        coll.allFiltersValue = allFiltersValue;
+        Optional.ofNullable(values).ifPresent(vs -> vs.forEach(coll::addValue));
+        if (doSeal) {
+            coll.seal();
+        }
+        return coll;
+    }
+
+    /**
+     * Returns the item counts per filter.
+     * If this object is sealed, a defensive copy will be returned.
+     *
+     * @return the item counts per filter
+     */
+    public Map<Filter, Integer> getValues() {
+        if (sealed) {
+            return new EnumMap<>(values);
+        }
+        return values;
+    }
+
+    /**
+     * Increments a filtered item count for a given filter.
+     *
+     * @param filter Filter to add to the requested filters in this collection
+     * @param delta Number by which the filtered item count must be incremented
+     * for the requested filter
+     */
+    public void addValue(Filter filter, int delta) {
+        checkSealed();
+        Integer oldValue = values.getOrDefault(filter, Integer.valueOf(0));
+        int newValue = oldValue.intValue() + delta;
+        values.put(filter, Integer.valueOf(newValue));
+    }
+
+    /**
+     * Sets all filtered item counts for this collection.
+     * The contents are copied into this object's internal Map, which is protected against
+     * further tampering with the provided Map.
+     *
+     * @param values Values that replace the current ones
+     */
+    public void setValues(Map<? extends Filter, ? extends Integer> values) {
+        checkSealed();
+        this.values.clear();
+        this.values.putAll(values);
+    }
+
+    public String getLabel() {
+        return label;
+    }
+
+    public void setLabel(String label) {
+        checkSealed();
+        this.label = label;
+    }
+
+    public String getHandle() {
+        return handle;
+    }
+
+    public void setHandle(String handle) {
+        checkSealed();
+        this.handle = handle;
+    }
+
+    public String getCommunityLabel() {
+        return communityLabel;
+    }
+
+    public void setCommunityLabel(String communityLabel) {
+        checkSealed();
+        this.communityLabel = communityLabel;
+    }
+
+    public String getCommunityHandle() {
+        return communityHandle;
+    }
+
+    public void setCommunityHandle(String communityHandle) {
+        checkSealed();
+        this.communityHandle = communityHandle;
+    }
+
+    public int getTotalItems() {
+        return totalItems;
+    }
+
+    public void setTotalItems(int totalItems) {
+        checkSealed();
+        this.totalItems = totalItems;
+    }
+
+    public int getAllFiltersValue() {
+        return allFiltersValue;
+    }
+
+    /**
+     * Increments the count of items matching all filters.
+     *
+     * @param delta Number by which the count must be incremented
+     */
+    public void addAllFiltersValue(int delta) {
+        checkSealed();
+        allFiltersValue++;
+    }
+
+    /**
+     * Replaces the count of items matching all filters.
+     *
+     * @param allFiltersValue Number that replaces the current item count
+     */
+    public void setAllFiltersValue(int allFiltersValue) {
+        checkSealed();
+        this.allFiltersValue = allFiltersValue;
+    }
+
+    public boolean getSealed() {
+        return sealed;
+    }
+
+    /**
+     * Seals this filtered collection object.
+     * No changes to this object can be made afterwards. Any attempt will throw
+     * an IllegalStateException.
+     */
+    public void seal() {
+        sealed = true;
+    }
+
+    private void checkSealed() {
+        if (sealed) {
+            throw new IllegalStateException("This filtered collection record is sealed"
+                    + " and cannot be modified anymore. You can apply changes to a non-sealed clone.");
+        }
+    }
+
+    /**
+     * Returns a non-sealed clone of this filtered collection record.
+     *
+     * @return a new non-sealed FilteredCollectionRest instance containing
+     * all attribute values of this object
+     */
+    @Override
+    public FilteredCollection clone() {
+        var clone = new FilteredCollection();
+        clone.label = label;
+        clone.handle = handle;
+        clone.values.putAll(values);
+        clone.allFiltersValue = allFiltersValue;
+        return clone;
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/FilteredCollections.java

@@ -0,0 +1,107 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * This class represents the complete result of a Filtered Collections report query.
+ * In addition to the list of FilteredCollection entries, it contains the lazily computed
+ * summary to be included in the completed report.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredCollections implements Serializable {
+
+    private static final long serialVersionUID = 3622651208704009095L;
+
+    /** Collections included in the report */
+    private List<FilteredCollection> collections = new ArrayList<>();
+    /**
+     * Summary generated by adding up data for each filter included in the report.
+     * It will be regenerated if any non-sealed collection item is found in
+     * the {@link #collections} collection attribute.
+     */
+    private FilteredCollection summary;
+
+    /**
+     * Shortcut method that builds a FilteredCollectionsRest instance
+     * from its building blocks.
+     * @param collections a list of FilteredCollectionRest instances
+     * @return a FilteredCollectionsRest instance built from the provided parameters
+     */
+    public static FilteredCollections of(Collection<FilteredCollection> collections) {
+        var colls = new FilteredCollections();
+        Optional.ofNullable(collections).ifPresent(cs -> cs.stream().forEach(colls::addCollection));
+        return colls;
+    }
+
+    /**
+     * Returns a defensive copy of the collections included in this report.
+     *
+     * @return the collections included in this report
+     */
+    public List<FilteredCollection> getCollections() {
+        return new ArrayList<>(collections);
+    }
+
+    /**
+     * Adds a {@link FilteredCollectionRest} object to this report.
+     *
+     * @param coll {@link FilteredCollectionRest} to add to this report
+     */
+    public void addCollection(FilteredCollection coll) {
+        summary = null;
+        collections.add(coll);
+    }
+
+    /**
+     * Sets all collections for this report.
+     * The contents are copied into this object's internal list, which is protected against
+     * further tampering with the provided list.
+     *
+     * @param collections Values that replace the current ones
+     */
+    public void setCollections(List<FilteredCollection> collections) {
+        summary = null;
+        this.collections.clear();
+        this.collections.addAll(collections);
+    }
+
+    /**
+     * Returns the report summary.
+     * If the summary has not been computed yet and/or the report includes non-sealed collections,
+     * it will be regenerated.
+     *
+     * @return the generated report summary
+     */
+    public FilteredCollection getSummary() {
+        boolean needsRefresh = summary == null || collections.stream().anyMatch(c -> !c.getSealed());
+        if (needsRefresh) {
+            summary = new FilteredCollection();
+            for (var coll : collections) {
+                coll.getValues().forEach(summary::addValue);
+            }
+            int total = collections.stream()
+                    .mapToInt(FilteredCollection::getTotalItems)
+                    .sum();
+            summary.setTotalItems(total);
+            int allFilters = collections.stream()
+                    .mapToInt(FilteredCollection::getAllFiltersValue)
+                    .sum();
+            summary.setAllFiltersValue(allFilters);
+            summary.seal();
+        }
+        return summary;
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/FilteredItems.java

@@ -0,0 +1,70 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.dspace.content.Item;
+
+/**
+ * This class represents a list of items for a  Filtered Items report query.
+ * Since the underlying list should correspond to only a page of results,
+ * the total number of items found through the query is included in this report.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredItems implements Serializable {
+
+    private static final long serialVersionUID = 7980375013177658249L;
+
+    /** Items included in the report */
+    private List<Item> items = new ArrayList<>();
+    /** Total item count (for pagination) */
+    private long itemCount;
+
+    /**
+     * Returns a defensive copy of the items included in this report.
+     *
+     * @return the items included in this report
+     */
+    public List<Item> getItems() {
+        return new ArrayList<>(items);
+    }
+
+    /**
+     * Adds an {@link ItemRest} object to this report.
+     *
+     * @param item {@link ItemRest} to add to this report
+     */
+    public void addItem(Item item) {
+        items.add(item);
+    }
+
+    /**
+     * Sets all items for this report.
+     * The contents are copied into this object's internal list, which is protected
+     * against further tampering with the provided list.
+     *
+     * @param items Values that replace the current ones
+     */
+    public void setItems(List<Item> items) {
+        this.items.clear();
+        this.items.addAll(items);
+    }
+
+    public long getItemCount() {
+        return itemCount;
+    }
+
+    public void setItemCount(long itemCount) {
+        this.itemCount = itemCount;
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/FilteredItemsQuery.java

@@ -0,0 +1,115 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+
+/**
+ * Structured query contents for the Filtered Items report
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredItemsQuery {
+
+    private List<String> collections = new ArrayList<>();
+    private List<QueryPredicate> queryPredicates = new ArrayList<>();
+    private long offset;
+    private int pageLimit;
+    private Set<Filter> filters = EnumSet.noneOf(Filter.class);
+    private List<String> additionalFields = new ArrayList<>();
+
+    /**
+     * Shortcut method that builds a FilteredItemsQuery instance
+     * from its building blocks.
+     * @param collectionUuids collection UUIDs to add
+     * @param predicates query predicates used to filter existing items
+     * @param pageLimit number of items per page
+     * @param filters filters to apply to existing items
+     * The filters mapping to true will be applied, others (either missing or
+     * mapping to false) will not.
+     * @param additionalFields additional fields to display in the resulting report
+     * @return a FilteredItemsQuery instance built from the provided parameters
+     */
+    public static FilteredItemsQuery of(Collection<String> collectionUuids,
+            Collection<QueryPredicate> predicates, long offset, int pageLimit,
+            Collection<Filter> filters, Collection<String> additionalFields) {
+        var query = new FilteredItemsQuery();
+        Optional.ofNullable(collectionUuids).ifPresent(query.collections::addAll);
+        Optional.ofNullable(predicates).ifPresent(query.queryPredicates::addAll);
+        query.offset = offset;
+        query.pageLimit = pageLimit;
+        Optional.ofNullable(filters).ifPresent(query.filters::addAll);
+        Optional.ofNullable(additionalFields).ifPresent(query.additionalFields::addAll);
+        return query;
+    }
+
+    public List<String> getCollections() {
+        return collections;
+    }
+
+    public void setCollections(List<String> collections) {
+        this.collections.clear();
+        if (collections != null) {
+            this.collections.addAll(collections);
+        }
+    }
+
+    public List<QueryPredicate> getQueryPredicates() {
+        return queryPredicates;
+    }
+
+    public void setQueryPredicates(List<QueryPredicate> queryPredicates) {
+        this.queryPredicates.clear();
+        if (queryPredicates != null) {
+            this.queryPredicates.addAll(queryPredicates);
+        }
+    }
+
+    public long getOffset() {
+        return offset;
+    }
+
+    public void setOffset(long offset) {
+        this.offset = offset;
+    }
+
+    public int getPageLimit() {
+        return pageLimit;
+    }
+
+    public void setPageLimit(int pageLimit) {
+        this.pageLimit = pageLimit;
+    }
+
+    public Set<Filter> getFilters() {
+        return filters;
+    }
+
+    public void setFilters(Set<Filter> filters) {
+        this.filters.clear();
+        if (filters != null) {
+            this.filters.addAll(filters);
+        }
+    }
+
+    public List<String> getAdditionalFields() {
+        return additionalFields;
+    }
+
+    public void setAdditionalFields(List<String> additionalFields) {
+        this.additionalFields.clear();
+        if (additionalFields != null) {
+            this.additionalFields.addAll(additionalFields);
+        }
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/ItemFilterUtil.java

@@ -0,0 +1,353 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import static org.dspace.content.Item.ANY;
+
+import java.sql.SQLException;
+import java.util.Arrays;
+import java.util.Calendar;
+import java.util.List;
+import java.util.Set;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.dspace.content.Bitstream;
+import org.dspace.content.Bundle;
+import org.dspace.content.Item;
+import org.dspace.content.factory.ContentServiceFactory;
+import org.dspace.content.service.ItemService;
+import org.dspace.core.Context;
+import org.dspace.services.factory.DSpaceServicesFactory;
+
+/**
+ * Utility methods for applying some of the filters defined in the {@link Filter} enum.
+ *
+ * @author Jean-François Morin (Université Laval) (port to DSpace 7.x)
+ * @author Terry Brady, Georgetown University (original code in DSpace 6.x)
+ */
+public class ItemFilterUtil {
+
+    protected static ItemService itemService = ContentServiceFactory.getInstance().getItemService();
+    private static final Logger log = LogManager.getLogger(ItemFilterUtil.class);
+    public static final String[] MIMES_PDF = {"application/pdf"};
+    public static final String[] MIMES_JPG = {"image/jpeg"};
+
+    /**
+     * Supported bundle types.
+     * N.B.: Bundle names are used in metadata as they are named here.
+     * Do NOT change these names, the name() method is invoked at multiple
+     * locations in this class and enum Filter.
+     * If these names are to change, the name() invocations shall be changed
+     * so that they refer to these unchanged names, likely through a String property.
+     */
+    enum BundleName {
+        ORIGINAL, TEXT, LICENSE, THUMBNAIL;
+    }
+
+    private ItemFilterUtil() {}
+
+    static String[] getDocumentMimeTypes() {
+        return DSpaceServicesFactory.getInstance().getConfigurationService()
+                .getArrayProperty("rest.report-mime-document");
+    }
+
+    static String[] getSupportedDocumentMimeTypes() {
+        return DSpaceServicesFactory.getInstance().getConfigurationService()
+                .getArrayProperty("rest.report-mime-document-supported");
+    }
+
+    static String[] getSupportedImageMimeTypes() {
+        return DSpaceServicesFactory.getInstance().getConfigurationService()
+                .getArrayProperty("rest.report-mime-document-image");
+    }
+
+    /**
+     * Counts the original bitstreams of a given item.
+     * @param item Provided item
+     * @return the number of original bitstreams in the item
+     */
+    static int countOriginalBitstream(Item item) {
+        return countBitstream(BundleName.ORIGINAL, item);
+    }
+
+    /**
+     * Counts the bitstreams of a given item for a specific type.
+     * @param bundleName Type of bundle to filter bitstreams
+     * @param item Provided item
+     * @return the number of matching bitstreams in the item
+     */
+    static int countBitstream(BundleName bundleName, Item item) {
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(bundleName.name()))
+                .mapToInt(bundle -> bundle.getBitstreams().size())
+                .sum();
+    }
+
+    /**
+     * Retrieves the bitstream names of an given item for a specific bundle type.
+     * @param bundleName Type of bundle to filter bitstreams
+     * @param item Provided item
+     * @return the names of matching bitstreams in the item
+     */
+    static List<String> getBitstreamNames(BundleName bundleName, Item item) {
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(bundleName.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .map(Bitstream::getName)
+                .collect(Collectors.toList());
+    }
+
+    /**
+     * Counts the original bitstreams of a given item matching one of a list of specific MIME types.
+     * @param context DSpace context
+     * @param item Provided item
+     * @param mimeList List of MIME types to filter bitstreams
+     * @return number of matching original bitstreams
+     */
+    static int countOriginalBitstreamMime(Context context, Item item, String[] mimeList) {
+        return countBitstreamMime(context, BundleName.ORIGINAL, item, mimeList);
+    }
+
+    /**
+     * Counts the bitstreams of a given item for a specific type matching one of a list of specific MIME types.
+     * @param context DSpace context
+     * @param bundleName Type of bundle to filter bitstreams
+     * @param item Provided item
+     * @param mimeList List of MIME types to filter bitstreams
+     * @return number of matching bitstreams
+     */
+    static int countBitstreamMime(Context context, BundleName bundleName, Item item, String[] mimeList) {
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(bundleName.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .mapToInt(bit -> {
+                    int count = 0;
+                    for (String mime : mimeList) {
+                        try {
+                            if (bit.getFormat(context).getMIMEType().equals(mime.trim())) {
+                                count++;
+                            }
+                        } catch (SQLException e) {
+                            log.error("Get format error for bitstream " + bit.getName());
+                        }
+                    }
+                    return count;
+                })
+                .sum();
+    }
+
+    /**
+     * Counts the bitstreams of a given item for a specific type matching one of a list of specific descriptions.
+     * @param bundleName Type of bundle to filter bitstreams
+     * @param item Provided item
+     * @param descList List of descriptions to filter bitstreams
+     * @return number of matching bitstreams
+     */
+    static int countBitstreamByDesc(BundleName bundleName, Item item, String[] descList) {
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(bundleName.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .filter(bit -> bit.getDescription() != null)
+                .mapToInt(bit -> {
+                    int count = 0;
+                    for (String desc : descList) {
+                        String bitDesc = bit.getDescription();
+                        if (bitDesc.equals(desc.trim())) {
+                            count++;
+                        }
+                    }
+                    return count;
+                })
+                .sum();
+    }
+
+    /**
+     * Counts the bitstreams of a given item smaller than a given size for a specific type
+     * matching one of a list of specific MIME types.
+     * @param context DSpace context
+     * @param bundleName Type of bundle to filter bitstreams
+     * @param item Provided item
+     * @param mimeList List of MIME types to filter bitstreams
+     * @param prop Configurable property providing the size to filter bitstreams
+     * @return number of matching bitstreams
+     */
+    static int countBitstreamSmallerThanMinSize(
+            Context context, BundleName bundleName, Item item, String[] mimeList, String prop) {
+        long size = DSpaceServicesFactory.getInstance().getConfigurationService().getLongProperty(prop);
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(bundleName.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .mapToInt(bit -> {
+                    int count = 0;
+                    for (String mime : mimeList) {
+                        try {
+                            if (bit.getFormat(context).getMIMEType().equals(mime.trim())) {
+                                if (bit.getSizeBytes() < size) {
+                                    count++;
+                                }
+                            }
+                        } catch (SQLException e) {
+                            log.error(e.getMessage(), e);
+                        }
+                    }
+                    return count;
+                })
+                .sum();
+    }
+
+    /**
+     * Counts the bitstreams of a given item larger than a given size for a specific type
+     * matching one of a list of specific MIME types.
+     * @param context DSpace context
+     * @param bundleName Type of bundle to filter bitstreams
+     * @param item Provided item
+     * @param mimeList List of MIME types to filter bitstreams
+     * @param prop Configurable property providing the size to filter bitstreams
+     * @return number of matching bitstreams
+     */
+    static int countBitstreamLargerThanMaxSize(
+            Context context, BundleName bundleName, Item item, String[] mimeList, String prop) {
+        long size = DSpaceServicesFactory.getInstance().getConfigurationService().getLongProperty(prop);
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(bundleName.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .mapToInt(bit -> {
+                    int count = 0;
+                    for (String mime : mimeList) {
+                        try {
+                            if (bit.getFormat(context).getMIMEType().equals(mime.trim())) {
+                                if (bit.getSizeBytes() > size) {
+                                    count++;
+                                }
+                            }
+                        } catch (SQLException e) {
+                            log.error(e.getMessage(), e);
+                        }
+                    }
+                    return count;
+                })
+                .sum();
+    }
+
+    /**
+     * Counts the original bitstreams of a given item whose MIME type starts with a specific prefix.
+     * @param context DSpace context
+     * @param item Provided item
+     * @param prefix Prefix to filter bitstreams
+     * @return number of matching original bitstreams
+     */
+    static int countOriginalBitstreamMimeStartsWith(Context context, Item item, String prefix) {
+        return countBitstreamMimeStartsWith(context, BundleName.ORIGINAL, item, prefix);
+    }
+
+    /**
+     * Counts the bitstreams of a given item for a specific type whose MIME type starts with a specific prefix.
+     * @param context DSpace context
+     * @param bundleName Type of bundle to filter bitstreams
+     * @param item Provided item
+     * @param prefix Prefix to filter bitstreams
+     * @return number of matching bitstreams
+     */
+    static int countBitstreamMimeStartsWith(Context context, BundleName bundleName, Item item, String prefix) {
+        return item.getBundles().stream()
+                .filter(bundle -> bundle.getName().equals(bundleName.name()))
+                .map(Bundle::getBitstreams)
+                .flatMap(List::stream)
+                .mapToInt(bit -> {
+                    int count = 0;
+                    try {
+                        if (bit.getFormat(context).getMIMEType().startsWith(prefix)) {
+                            count++;
+                        }
+                    } catch (SQLException e) {
+                        log.error(e.getMessage(), e);
+                    }
+                    return count;
+                })
+                .sum();
+    }
+
+    /**
+     * Returns true if a given item has a bundle not matching a specific list of bundles.
+     * @param item Provided item
+     * @param bundleList List of bundle names to filter bundles
+     * @return true if the item has a (non-)matching bundle
+     */
+    static boolean hasUnsupportedBundle(Item item, String[] bundleList) {
+        if (bundleList == null) {
+            return false;
+        }
+        Set<String> bundles = Arrays.stream(bundleList)
+                .collect(Collectors.toSet());
+        return item.getBundles().stream()
+                .anyMatch(bundle -> !bundles.contains(bundle.getName()));
+    }
+
+    static boolean hasOriginalBitstreamMime(Context context, Item item, String[] mimeList) {
+        return hasBitstreamMime(context, BundleName.ORIGINAL, item, mimeList);
+    }
+
+    static boolean hasBitstreamMime(Context context, BundleName bundleName, Item item, String[] mimeList) {
+        return countBitstreamMime(context, bundleName, item, mimeList) > 0;
+    }
+
+    /**
+     * Returns true if a given item has at least one field of a specific list whose value
+     * matches a provided regular expression.
+     * @param item Provided item
+     * @param fieldList List of fields to check
+     * @param regex Regular expression to check field values against
+     * @return true if there is at least one matching field, false otherwise
+     */
+    static boolean hasMetadataMatch(Item item, String fieldList, Pattern regex) {
+        if ("*".equals(fieldList)) {
+            return itemService.getMetadata(item, ANY, ANY, ANY, ANY).stream()
+                    .anyMatch(md -> regex.matcher(md.getValue()).matches());
+        }
+
+        return Arrays.stream(fieldList.split(","))
+                .map(field -> itemService.getMetadataByMetadataString(item, field.trim()))
+                .flatMap(List::stream)
+                .anyMatch(md -> regex.matcher(md.getValue()).matches());
+    }
+
+    /**
+     * Returns true if a given item has at all fields of a specific list whose values
+     * match a provided regular expression.
+     * @param item Provided item
+     * @param fieldList List of fields to check
+     * @param regex Regular expression to check field values against
+     * @return true if all specified fields match, false otherwise
+     */
+    static boolean hasOnlyMetadataMatch(Item item, String fieldList, Pattern regex) {
+        if ("*".equals(fieldList)) {
+            return itemService.getMetadata(item, ANY, ANY, ANY, ANY).stream()
+                    .allMatch(md -> regex.matcher(md.getValue()).matches());
+        }
+
+        return Arrays.stream(fieldList.split(","))
+                .map(field -> itemService.getMetadataByMetadataString(item, field.trim()))
+                .flatMap(List::stream)
+                .allMatch(md -> regex.matcher(md.getValue()).matches());
+    }
+
+    static boolean recentlyModified(Item item, int days) {
+        Calendar cal = Calendar.getInstance();
+        cal.add(Calendar.DATE, -days);
+        return cal.getTime().before(item.getLastModified());
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/QueryOperator.java

@@ -0,0 +1,131 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.util.Arrays;
+import java.util.function.BiFunction;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.Expression;
+import javax.persistence.criteria.Path;
+import javax.persistence.criteria.Predicate;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.apache.commons.lang3.function.TriFunction;
+import org.dspace.content.MetadataValue;
+import org.dspace.content.MetadataValue_;
+import org.dspace.util.DSpacePostgreSQLDialect;
+import org.dspace.util.JpaCriteriaBuilderKit;
+import org.hibernate.criterion.Criterion;
+import org.hibernate.criterion.Property;
+import org.hibernate.criterion.Restrictions;
+import org.hibernate.type.StandardBasicTypes;
+
+/**
+ * Operators available for creating predicates to query the
+ * Filtered Items report
+ * @author Jean-François Morin (Université Laval)
+ */
+public enum QueryOperator {
+
+    EXISTS("exists", true, false,
+        (val, regexClause) -> Property.forName("mv.value").isNotNull(),
+        (val, regexClause, jpaKit) -> jpaKit.criteriaBuilder().isNotNull(jpaKit.root().get(MetadataValue_.VALUE))),
+    DOES_NOT_EXIST("doesnt_exist", true, true,
+        (val, regexClause) -> EXISTS.buildPredicate(val, regexClause),
+        (val, regexClause, jpaKit) -> EXISTS.buildJpaPredicate(val, regexClause, jpaKit)),
+    EQUALS("equals", true, false,
+        (val, regexClause) -> Property.forName("mv.value").eq(val),
+        (val, regexClause, jpaKit) -> jpaKit.criteriaBuilder().equal(jpaKit.root().get(MetadataValue_.VALUE), val)),
+    DOES_NOT_EQUAL("not_equals", true, true,
+        (val, regexClause) -> EQUALS.buildPredicate(val, regexClause),
+        (val, regexClause, jpaKit) -> EQUALS.buildJpaPredicate(val, regexClause, jpaKit)),
+    LIKE("like", true, false,
+        (val, regexClause) -> Property.forName("mv.value").like(val),
+        (val, regexClause, jpaKit) -> jpaKit.criteriaBuilder().like(jpaKit.root().get(MetadataValue_.VALUE), val)),
+    NOT_LIKE("not_like", true, true,
+        (val, regexClause) -> LIKE.buildPredicate(val, regexClause),
+        (val, regexClause, jpaKit) -> LIKE.buildJpaPredicate(val, regexClause, jpaKit)),
+    CONTAINS("contains", true, false,
+        (val, regexClause) -> Property.forName("mv.value").like("%" + val + "%"),
+        (val, regexClause, jpaKit) -> LIKE.buildJpaPredicate("%" + val + "%", regexClause, jpaKit)),
+    DOES_NOT_CONTAIN("doesnt_contain", true, true,
+        (val, regexClause) -> CONTAINS.buildPredicate(val, regexClause),
+        (val, regexClause, jpaKit) -> CONTAINS.buildJpaPredicate(val, regexClause, jpaKit)),
+    MATCHES("matches", false, false,
+        (val, regexClause) -> Restrictions.sqlRestriction(regexClause, val, StandardBasicTypes.STRING),
+        (val, regexClause, jpaKit) -> regexPredicate(val, DSpacePostgreSQLDialect.REGEX_MATCHES, jpaKit)),
+    DOES_NOT_MATCH("doesnt_match", false, false,
+        (val, regexClause) -> Restrictions.not(Restrictions.sqlRestriction(
+                regexClause, val, StandardBasicTypes.STRING)),
+        (val, regexClause, jpaKit) -> regexPredicate(val, DSpacePostgreSQLDialect.REGEX_NOT_MATCHES, jpaKit));
+
+    private final String code;
+    /** Criteria builder for the old Hibernate API */
+    @Deprecated(forRemoval = true)
+    private final BiFunction<String, String, Criterion> criterionBuilder;
+    private final TriFunction<String, String, JpaCriteriaBuilderKit<MetadataValue>, Predicate> predicateBuilder;
+    private final boolean usesRegex;
+    private final boolean negate;
+
+    QueryOperator(String code, boolean usesRegex, boolean negate,
+            BiFunction<String, String, Criterion> criterionBuilder,
+            TriFunction<String, String, JpaCriteriaBuilderKit<MetadataValue>, Predicate> predicateBuilder) {
+        this.code = code;
+        this.usesRegex = usesRegex;
+        this.negate = negate;
+        this.criterionBuilder = criterionBuilder;
+        this.predicateBuilder = predicateBuilder;
+    }
+
+    @JsonProperty
+    public String getCode() {
+        return code;
+    }
+
+    public boolean getUsesRegex() {
+        return usesRegex;
+    }
+
+    public boolean getNegate() {
+        return negate;
+    }
+
+    public Criterion buildPredicate(String val, String regexClause) {
+        return criterionBuilder.apply(val, regexClause);
+    }
+
+    public Predicate buildJpaPredicate(String val, String regexClause, JpaCriteriaBuilderKit<MetadataValue> jpaKit) {
+        return predicateBuilder.apply(val, regexClause, jpaKit);
+    }
+
+    @JsonCreator
+    public static QueryOperator get(String code) {
+        return Arrays.stream(values())
+                .filter(item -> item.code.equalsIgnoreCase(code))
+                .findFirst()
+                .orElse(null);
+    }
+
+    public BiFunction<String, String, Criterion> getCriterionBuilder() {
+        return criterionBuilder;
+    }
+
+    private static Predicate regexPredicate(String val, String regexFunction,
+            JpaCriteriaBuilderKit<MetadataValue> jpaKit) {
+        // Source: https://stackoverflow.com/questions/24995881/use-regular-expressions-in-jpa-criteriabuilder
+        CriteriaBuilder builder = jpaKit.criteriaBuilder();
+        Expression<String> patternExpression = builder.<String>literal(val);
+        Path<String> path = jpaKit.root().get(MetadataValue_.VALUE);
+        // "matches" comes from the name of the regex function
+        // defined in class DSpacePostgreSQLDialect
+        return builder.equal(builder
+                .function(regexFunction, Boolean.class, path, patternExpression), Boolean.TRUE);
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/QueryPredicate.java

@@ -0,0 +1,69 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import org.dspace.content.MetadataField;
+
+/**
+ * Data structure representing a query predicate used by the Filtered Items report
+ * to filter items to retrieve.
+ * @author Jean-François Morin (Université Laval)
+ */
+public class QueryPredicate {
+
+    private List<MetadataField> fields = new ArrayList<>();
+    private QueryOperator operator;
+    private String value;
+
+    /**
+     * Shortcut method that builds a QueryPredicate from a single field, an operator, and a value.
+     * @param field Predicate subject
+     * @param operator Predicate operator
+     * @param value Predicate object
+     * @return a QueryPredicate instance built from the provided parameters
+     */
+    public static QueryPredicate of(MetadataField field, QueryOperator operator, String value) {
+        var predicate = new QueryPredicate();
+        predicate.fields.add(field);
+        predicate.operator = operator;
+        predicate.value = value;
+        return predicate;
+    }
+
+    /**
+     * Shortcut method that builds a QueryPredicate from a list of fields, an operator, and a value.
+     * @param fields Fields that form the predicate subject
+     * @param operator Predicate operator
+     * @param value Predicate object
+     * @return a QueryPredicate instance built from the provided parameters
+     */
+    public static QueryPredicate of(Collection<MetadataField> fields, QueryOperator operator, String value) {
+        var predicate = new QueryPredicate();
+        predicate.fields.addAll(fields);
+        predicate.operator = operator;
+        predicate.value = value;
+        return predicate;
+    }
+
+    public List<MetadataField> getFields() {
+        return fields;
+    }
+
+    public QueryOperator getOperator() {
+        return operator;
+    }
+
+    public String getValue() {
+        return value;
+    }
+
+}

dspace-api/src/main/java/org/dspace/contentreport/service/ContentReportService.java

@@ -0,0 +1,55 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.contentreport.service;
+
+import java.sql.SQLException;
+import java.util.Collection;
+import java.util.List;
+
+import org.dspace.content.MetadataField;
+import org.dspace.contentreport.Filter;
+import org.dspace.contentreport.FilteredCollection;
+import org.dspace.contentreport.FilteredItems;
+import org.dspace.contentreport.FilteredItemsQuery;
+import org.dspace.core.Context;
+
+public interface ContentReportService {
+
+    /**
+     * Returns <code>true<</code> if Content Reports are enabled.
+     * @return <code>true<</code> if Content Reports are enabled
+     */
+    boolean getEnabled();
+
+    /**
+     * Retrieves item statistics per collection according to a set of Boolean filters.
+     * @param context DSpace context
+     * @param filters Set of filters
+     * @return a list of collections with the requested statistics for each of them
+     */
+    List<FilteredCollection> findFilteredCollections(Context context, Collection<Filter> filters);
+
+    /**
+     * Retrieves a list of items according to a set of criteria.
+     * @param context DSpace context
+     * @param query structured query to find items against
+     * @return a list of items filtered according to the provided query
+     */
+    FilteredItems findFilteredItems(Context context, FilteredItemsQuery query);
+
+    /**
+     * Converts a metadata field name to a list of {@link MetadataField} instances
+     * (one if no wildcards are used, possibly more otherwise).
+     * @param context DSpace context
+     * @param metadataField field to search for
+     * @return a corresponding list of {@link MetadataField} entries
+     */
+    List<MetadataField> getMetadataFields(org.dspace.core.Context context, String metadataField)
+            throws SQLException;
+
+}

dspace-api/src/main/java/org/dspace/util/DSpacePostgreSQLDialect.java

@@ -0,0 +1,33 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.util;
+
+import org.hibernate.dialect.PostgreSQL94Dialect;
+import org.hibernate.dialect.function.SQLFunctionTemplate;
+import org.hibernate.type.StandardBasicTypes;
+
+/**
+ * PostgreSQL-specific dialect that adds regular expression support as a JPA function.
+ * @see org.dspace.contentreport.QueryOperator
+ * @author Jean-François Morin (Université Laval)
+ */
+public class DSpacePostgreSQLDialect extends PostgreSQL94Dialect {
+
+    public static final String REGEX_MATCHES = "matches";
+    public static final String REGEX_IMATCHES = "imatches";
+    public static final String REGEX_NOT_MATCHES = "not_matches";
+    public static final String REGEX_NOT_IMATCHES = "not_imatches";
+
+    public DSpacePostgreSQLDialect() {
+        registerFunction(REGEX_MATCHES, new SQLFunctionTemplate(StandardBasicTypes.BOOLEAN, "?1 ~ ?2"));
+        registerFunction(REGEX_IMATCHES, new SQLFunctionTemplate(StandardBasicTypes.BOOLEAN, "?1 ~* ?2"));
+        registerFunction(REGEX_NOT_MATCHES, new SQLFunctionTemplate(StandardBasicTypes.BOOLEAN, "?1 !~ ?2"));
+        registerFunction(REGEX_NOT_IMATCHES, new SQLFunctionTemplate(StandardBasicTypes.BOOLEAN, "?1 !~* ?2"));
+    }
+
+}

dspace-api/src/main/java/org/dspace/util/JpaCriteriaBuilderKit.java

@@ -0,0 +1,49 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.util;
+
+import javax.persistence.criteria.AbstractQuery;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.Root;
+
+/**
+ * Data structure containing the required objects to build criteria
+ * for a JPA query built using the JPA Criteria API.
+ * The getters match those generated by the JVM when using a record
+ * so that no API changes will be required when this class gets converted
+ * into a record when DSpace gets promoted to Java 17 or later.
+ * @author Jean-François Morin (Université Laval)
+ */
+// TODO: Convert this data structure into a record when DSpace gets promoted to Java 17 or later
+public class JpaCriteriaBuilderKit<T> {
+
+    private CriteriaBuilder criteriaBuilder;
+    /** Can be a CriteriaQuery as well as a Subquery - both extend AbstractQuery. */
+    private AbstractQuery<T> query;
+    private Root<T> root;
+
+    public JpaCriteriaBuilderKit(CriteriaBuilder criteriaBuilder, AbstractQuery<T> query,
+            Root<T> root) {
+        this.criteriaBuilder = criteriaBuilder;
+        this.query = query;
+        this.root = root;
+    }
+
+    public CriteriaBuilder criteriaBuilder() {
+        return criteriaBuilder;
+    }
+
+    public AbstractQuery<T> query() {
+        return query;
+    }
+
+    public Root<T> root() {
+        return root;
+    }
+
+}

dspace-api/src/test/java/org/dspace/AbstractIntegrationTestWithDatabase.java

@@ -9,7 +9,10 @@ package org.dspace;
 
 import static org.junit.Assert.fail;
 
+import java.sql.Connection;
 import java.sql.SQLException;
+import java.sql.Statement;
+import javax.sql.DataSource;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -91,6 +94,14 @@ public class AbstractIntegrationTestWithDatabase extends AbstractDSpaceIntegrati
         try {
             // Update/Initialize the database to latest version (via Flyway)
             DatabaseUtils.updateDatabase();
+
+            // Register custom functions in the H2 database
+            DataSource dataSource = DSpaceServicesFactory.getInstance()
+                    .getServiceManager()
+                    .getServiceByName("dataSource", DataSource.class);
+            try (Connection c = dataSource.getConnection(); Statement stmt = c.createStatement()) {
+                stmt.execute("CREATE ALIAS IF NOT EXISTS matches FOR 'org.dspace.util.DSpaceH2Dialect.matches'");
+            }
         } catch (SQLException se) {
             log.error("Error initializing database", se);
             fail("Error initializing database: " + se.getMessage()

dspace-api/src/test/java/org/dspace/content/service/ItemServiceIT.java

@@ -11,7 +11,9 @@ import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.hasSize;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
 import java.io.ByteArrayInputStream;
@@ -19,6 +21,9 @@ import java.io.InputStream;
 import java.sql.SQLException;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.UUID;
 import java.util.stream.Collectors;
 
 import org.apache.logging.log4j.Logger;
@@ -44,11 +49,15 @@ import org.dspace.content.Collection;
 import org.dspace.content.Community;
 import org.dspace.content.EntityType;
 import org.dspace.content.Item;
+import org.dspace.content.MetadataField;
+import org.dspace.content.MetadataSchema;
 import org.dspace.content.MetadataValue;
 import org.dspace.content.Relationship;
 import org.dspace.content.RelationshipType;
 import org.dspace.content.WorkspaceItem;
 import org.dspace.content.factory.ContentServiceFactory;
+import org.dspace.contentreport.QueryOperator;
+import org.dspace.contentreport.QueryPredicate;
 import org.dspace.core.Constants;
 import org.dspace.eperson.Group;
 import org.dspace.eperson.factory.EPersonServiceFactory;
@@ -71,6 +80,9 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
     protected ItemService itemService = ContentServiceFactory.getInstance().getItemService();
     protected InstallItemService installItemService = ContentServiceFactory.getInstance().getInstallItemService();
     protected WorkspaceItemService workspaceItemService = ContentServiceFactory.getInstance().getWorkspaceItemService();
+    protected MetadataSchemaService metadataSchemaService =
+            ContentServiceFactory.getInstance().getMetadataSchemaService();
+    protected MetadataFieldService metadataFieldService = ContentServiceFactory.getInstance().getMetadataFieldService();
     protected MetadataValueService metadataValueService = ContentServiceFactory.getInstance().getMetadataValueService();
     protected VersioningService versioningService = VersionServiceFactory.getInstance().getVersionService();
     protected AuthorizeService authorizeService = AuthorizeServiceFactory.getInstance().getAuthorizeService();
@@ -78,6 +90,8 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
 
     Community community;
     Collection collection1;
+    MetadataSchema schemaDC;
+    MetadataField fieldAuthor;
 
     Item item;
 
@@ -99,6 +113,9 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
         try {
             context.turnOffAuthorisationSystem();
 
+            schemaDC = metadataSchemaService.find(context, "dc");
+            fieldAuthor = metadataFieldService.findByElement(context, schemaDC, "contributor", "author");
+
             community = CommunityBuilder.createCommunity(context)
                 .build();
 
@@ -142,7 +159,7 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
 
         // check the correct order using default method `getMetadata`
         List<MetadataValue> defaultMetadata =
-            this.itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY);
+            itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY);
 
         assertThat(defaultMetadata,hasSize(3));
 
@@ -158,7 +175,7 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
 
         // check the correct order using the method `getMetadata` without virtual fields
         List<MetadataValue> nonVirtualMetadatas =
-            this.itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY, false);
+            itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY, false);
 
         // if we don't reload the item the place order is not applied correctly
         // item = context.reloadEntity(item);
@@ -180,19 +197,19 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
         item = context.reloadEntity(item);
 
         // now just add one metadata to be the last
-        this.itemService.addMetadata(
+        itemService.addMetadata(
             context, item, dcSchema, contributorElement, authorQualifier, Item.ANY, "test, latest", null, 0
         );
         // now just remove first metadata
-        this.itemService.removeMetadataValues(context, item, List.of(placeZero));
+        itemService.removeMetadataValues(context, item, List.of(placeZero));
         // now just add one metadata to place 0
-        this.itemService.addAndShiftRightMetadata(
+        itemService.addAndShiftRightMetadata(
             context, item, dcSchema, contributorElement, authorQualifier, Item.ANY, "test, new", null, 0, 0
         );
 
         // check the metadata using method `getMetadata`
         defaultMetadata =
-            this.itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY);
+            itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY);
 
         // check correct places
         assertThat(defaultMetadata,hasSize(4));
@@ -212,7 +229,7 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
 
         // check metadata using nonVirtualMethod
         nonVirtualMetadatas =
-            this.itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY, false);
+            itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY, false);
 
         // check correct places
         assertThat(nonVirtualMetadatas,hasSize(4));
@@ -244,7 +261,7 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
 
         // check after commit
         defaultMetadata =
-            this.itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY);
+            itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY);
 
         // check correct places
         assertThat(defaultMetadata,hasSize(4));
@@ -264,7 +281,7 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
 
         // check metadata using nonVirtualMethod
         nonVirtualMetadatas =
-            this.itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY, false);
+            itemService.getMetadata(item, dcSchema, contributorElement, authorQualifier, Item.ANY, false);
 
         // check correct places
         assertThat(nonVirtualMetadatas,hasSize(4));
@@ -916,4 +933,65 @@ public class ItemServiceIT extends AbstractIntegrationTestWithDatabase {
         assertThat(metadataValue.getAuthority(), equalTo(authority));
         assertThat(metadataValue.getPlace(), equalTo(place));
     }
+
+    @Test
+    public void testFindByMetadataQuery() throws Exception {
+        context.turnOffAuthorisationSystem();
+
+        // Here we add an author to the item
+        MetadataValue mv = itemService.addMetadata(context, item, dcSchema, contributorElement,
+                authorQualifier, null, "test, one");
+        context.commit();
+
+        item = context.reloadEntity(item);
+
+        assertNotNull(mv);
+        MetadataField mf = mv.getMetadataField();
+        assertEquals(fieldAuthor, mf);
+        MetadataSchema ms = mf.getMetadataSchema();
+        assertNotNull(ms);
+        assertEquals(dcSchema, ms.getName());
+
+        // We check whether the author metadata was properly added.
+        List<MetadataValue> mvs = item.getMetadata();
+        MetadataValue mvAuthor1 = mvs.stream()
+                .filter(mv1 -> Objects.equals(mv1.getMetadataField().getElement(), "contributor"))
+                .filter(mv1 -> Objects.equals(mv1.getMetadataField().getQualifier(), "author"))
+                .findFirst()
+                .orElse(null);
+        assertNotNull(mvAuthor1);
+        assertEquals("test, one", mvAuthor1.getValue());
+
+        assertMetadataValue(
+            authorQualifier, contributorElement, dcSchema, "test, one", null, 0, mvAuthor1
+        );
+
+        assertEquals(collection1, item.getOwningCollection());
+
+        List<UUID> collectionUuids = List.of(collection1.getID());
+
+        // First test: we should not find anything.
+        QueryPredicate predicate = QueryPredicate.of(fieldAuthor, QueryOperator.MATCHES, ".*whatever.*");
+        List<Item> items = itemService.findByMetadataQuery(context, List.of(predicate), collectionUuids, 0, -1);
+        assertTrue(items.isEmpty());
+
+        // Second test: we search against the metadata value specified above.
+        predicate = QueryPredicate.of(fieldAuthor, QueryOperator.EQUALS, "test, one");
+        items = itemService.findByMetadataQuery(context, List.of(predicate), collectionUuids, 0, -1);
+        assertEquals(1, items.size());
+
+        Item item = items.get(0);
+        assertNotNull(item);
+        List<MetadataValue> allMetadata = item.getMetadata();
+        Optional<MetadataValue> mvAuthor = allMetadata.stream()
+                .filter(md -> Objects.equals(dcSchema, md.getMetadataField().getMetadataSchema().getName()))
+                .filter(md -> Objects.equals(contributorElement, md.getMetadataField().getElement()))
+                .filter(md -> Objects.equals(authorQualifier, md.getMetadataField().getQualifier()))
+                .findFirst();
+        assertTrue(mvAuthor.isPresent());
+        assertEquals("test, one", mvAuthor.get().getValue());
+
+        context.restoreAuthSystemState();
+    }
+
 }

dspace-api/src/test/java/org/dspace/util/DSpaceH2Dialect.java

@@ -0,0 +1,41 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.util;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.regex.Pattern;
+
+import org.hibernate.dialect.H2Dialect;
+import org.hibernate.dialect.function.SQLFunctionTemplate;
+import org.hibernate.type.StandardBasicTypes;
+
+/**
+ * H2-specific dialect that adds regular expression support as a function.
+ * @author Jean-François Morin (Université Laval)
+ */
+public class DSpaceH2Dialect extends H2Dialect {
+
+    private static Map<String, Pattern> regexCache = new HashMap<>();
+
+    public DSpaceH2Dialect() {
+        registerFunction("matches", new SQLFunctionTemplate(StandardBasicTypes.BOOLEAN, "matches(?1, ?2)"));
+
+        // The SQL function is registered in AbstractIntegrationTestWithDatabase.initDatabase().
+    }
+
+    public static boolean matches(String regex, String value) {
+        Pattern pattern = regexCache.get(regex);
+        if (pattern == null) {
+            pattern = Pattern.compile(regex);
+            regexCache.put(regex, pattern);
+        }
+        return pattern.matcher(value).matches();
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/ContentReportRestController.java

@@ -0,0 +1,226 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest;
+
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.apache.commons.lang3.StringUtils;
+import org.apache.logging.log4j.Logger;
+import org.dspace.app.rest.converter.ConverterService;
+import org.dspace.app.rest.model.ContentReportSupportRest;
+import org.dspace.app.rest.model.FilteredCollectionsQuery;
+import org.dspace.app.rest.model.FilteredCollectionsRest;
+import org.dspace.app.rest.model.FilteredItemsQueryPredicate;
+import org.dspace.app.rest.model.FilteredItemsQueryRest;
+import org.dspace.app.rest.model.FilteredItemsRest;
+import org.dspace.app.rest.model.RestModel;
+import org.dspace.app.rest.model.hateoas.ContentReportSupportResource;
+import org.dspace.app.rest.model.hateoas.FilteredCollectionsResource;
+import org.dspace.app.rest.model.hateoas.FilteredItemsResource;
+import org.dspace.app.rest.repository.ContentReportRestRepository;
+import org.dspace.app.rest.utils.ContextUtil;
+import org.dspace.contentreport.Filter;
+import org.dspace.contentreport.service.ContentReportService;
+import org.dspace.core.Context;
+import org.springframework.beans.factory.InitializingBean;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Sort;
+import org.springframework.data.rest.webmvc.ControllerUtils;
+import org.springframework.hateoas.Link;
+import org.springframework.hateoas.RepresentationModel;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+
+/**
+ * This controller receives and dispatches requests related to the
+ * contents reports ported from DSpace 6.x (Filtered Collections
+ * and Filtered Items).
+ * @author Jean-François Morin (Université Laval)
+ */
+@RestController
+@RequestMapping("/api/" + RestModel.CONTENT_REPORT)
+public class ContentReportRestController implements InitializingBean {
+
+    private static final Logger log = org.apache.logging.log4j.LogManager.getLogger();
+
+    @Autowired
+    private DiscoverableEndpointsService discoverableEndpointsService;
+    @Autowired
+    private ConverterService converter;
+    @Autowired
+    private ContentReportRestRepository contentReportRestRepository;
+    @Autowired
+    private ContentReportService contentReportService;
+
+    @Override
+    public void afterPropertiesSet() throws Exception {
+        discoverableEndpointsService
+            .register(this, List.of(Link.of("/api/" + RestModel.CONTENT_REPORT, RestModel.CONTENT_REPORT)));
+    }
+
+    @RequestMapping(method = RequestMethod.GET)
+    public ContentReportSupportResource getContentReportSupport() {
+        ContentReportSupportRest contentReportSupportRest = contentReportRestRepository.getContentReportSupport();
+        return converter.toResource(contentReportSupportRest);
+    }
+
+    /**
+     * GET-based endpoint for the Filtered Collections contents report.
+     * This method also serves as a feed for the HAL Browser infrastructure.
+     * @param filters querying filters received as a comma-separated string
+     * or as a multivalued parameter
+     * @param request HTTP request
+     * @param response HTTP response
+     * @return the list of collections with their respective statistics
+     */
+    @PreAuthorize("hasAuthority('ADMIN')")
+    @GetMapping("/filteredcollections")
+    public ResponseEntity<RepresentationModel<?>> getFilteredCollections(
+            @RequestParam(name = "filters", required = false) List<String> filters,
+            HttpServletRequest request, HttpServletResponse response) throws IOException {
+        if (contentReportService.getEnabled()) {
+            Context context = ContextUtil.obtainContext(request);
+            Set<Filter> filtersSet = listToStream(filters)
+                    .map(Filter::get)
+                    .filter(f -> f != null)
+                    .collect(Collectors.toSet());
+            FilteredCollectionsQuery query = FilteredCollectionsQuery.of(filtersSet);
+            return filteredCollectionsReport(context, query);
+        }
+
+        error404(response);
+        return null;
+    }
+
+
+    private ResponseEntity<RepresentationModel<?>> filteredCollectionsReport(Context context,
+            FilteredCollectionsQuery query) {
+        FilteredCollectionsRest report = contentReportRestRepository
+                .findFilteredCollections(context, query);
+        FilteredCollectionsResource result = converter.toResource(report);
+        return ControllerUtils.toResponseEntity(HttpStatus.OK, new HttpHeaders(), result);
+    }
+
+    /**
+     * Endpoint for the Filtered Items contents report.
+     * All parameters received as comma-separated lists can also be repeated
+     * instead (e.g., filters=a&filters=b&...).
+     * @param collections comma-separated list UUIDs of collections to include in the report
+     * @param predicates predicates to filter the requested items.
+     * A given predicate has the form
+     * field:operator:value (if value is required by the operator), or
+     * field:operator (if no value is required by the operator).
+     * The colon is used here as a separator to avoid conflicts with the
+     * comma, which is already used by Spring as a multi-value separator.
+     * Predicates are actually retrieved directly through the request to prevent comma-containing
+     * predicate values from being split by the Spring infrastructure.
+     * @param pageNumber page number (starting at 0)
+     * @param pageLimit maximum number of items per page
+     * @param filters querying filters received as a comma-separated string
+     * @param additionalFields comma-separated list of extra fields to add to the report
+     * @param request HTTP request
+     * @param response HTTP response
+     * @param pageable paging parameters
+     * @return the list of items with their respective statistics
+     */
+    @PreAuthorize("hasAuthority('ADMIN')")
+    @GetMapping("/filtereditems")
+    public ResponseEntity<RepresentationModel<?>> getFilteredItems(
+            @RequestParam(name = "collections", required = false) List<String> collections,
+            @RequestParam(name = "queryPredicates", required = false) List<String> predicates,
+            @RequestParam(name = "pageNumber", defaultValue = "0") String pageNumber,
+            @RequestParam(name = "pageLimit", defaultValue = "10") String pageLimit,
+            @RequestParam(name = "filters", required = false) List<String> filters,
+            @RequestParam(name = "additionalFields", required = false) List<String> additionalFields,
+            HttpServletRequest request, HttpServletResponse response, Pageable pageable) throws IOException {
+        if (contentReportService.getEnabled()) {
+            Context context = ContextUtil.obtainContext(request);
+            String[] realPredicates = request.getParameterValues("queryPredicates");
+            List<String> collUuids = Optional.ofNullable(collections).orElseGet(() -> List.of());
+            List<FilteredItemsQueryPredicate> preds = arrayToStream(realPredicates)
+                    .map(FilteredItemsQueryPredicate::of)
+                    .collect(Collectors.toList());
+            int pgLimit = parseInt(pageLimit, 10);
+            int pgNumber = parseInt(pageNumber, 0);
+            Pageable myPageable = pageable;
+            if (pageable == null || pageable.getPageNumber() != pgNumber || pageable.getPageSize() != pgLimit) {
+                Sort sort = Optional.ofNullable(pageable).map(Pageable::getSort).orElse(Sort.unsorted());
+                myPageable = PageRequest.of(pgNumber, pgLimit, sort);
+            }
+            Set<Filter> filtersMap = listToStream(filters)
+                    .map(Filter::get)
+                    .filter(f -> f != null)
+                    .collect(Collectors.toSet());
+            List<String> addFields = Optional.ofNullable(additionalFields).orElseGet(() -> List.of());
+            FilteredItemsQueryRest query = FilteredItemsQueryRest.of(collUuids, preds, pgLimit, filtersMap, addFields);
+
+            return filteredItemsReport(context, query, myPageable);
+        }
+
+        error404(response);
+        return null;
+    }
+
+    private static Stream<String> listToStream(Collection<String> array) {
+        return Optional.ofNullable(array)
+                .stream()
+                .flatMap(Collection::stream)
+                .filter(StringUtils::isNotBlank);
+    }
+
+    private static Stream<String> arrayToStream(String... array) {
+        return Optional.ofNullable(array)
+                .stream()
+                .flatMap(Arrays::stream)
+                .filter(StringUtils::isNotBlank);
+    }
+
+    private static int parseInt(String value, int defaultValue) {
+        return Optional.ofNullable(value)
+                .stream()
+                .mapToInt(Integer::parseInt)
+                .findFirst()
+                .orElse(defaultValue);
+    }
+
+    private ResponseEntity<RepresentationModel<?>> filteredItemsReport(Context context,
+            FilteredItemsQueryRest query, Pageable pageable) {
+        FilteredItemsRest report = contentReportRestRepository
+                .findFilteredItems(context, query, pageable);
+        FilteredItemsResource result = converter.toResource(report);
+        return ControllerUtils.toResponseEntity(HttpStatus.OK, new HttpHeaders(), result);
+    }
+
+    private void error404(HttpServletResponse response) throws IOException {
+        log.debug("Content Reports are disabled");
+        String err = "Content Reports are disabled";
+        response.setStatus(404);
+        response.setContentType("text/html");
+        response.setContentLength(err.length());
+        response.getWriter().write(err);
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/converter/FilteredItemConverter.java

@@ -0,0 +1,125 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.converter;
+
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+
+import org.apache.commons.collections4.CollectionUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.apache.logging.log4j.Logger;
+import org.dspace.app.rest.model.FilteredItemRest;
+import org.dspace.app.rest.model.MetadataValueList;
+import org.dspace.app.rest.projection.Projection;
+import org.dspace.app.rest.utils.ContextUtil;
+import org.dspace.app.util.service.MetadataExposureService;
+import org.dspace.authorize.service.AuthorizeService;
+import org.dspace.content.Item;
+import org.dspace.content.MetadataField;
+import org.dspace.content.MetadataValue;
+import org.dspace.content.service.ItemService;
+import org.dspace.core.Context;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Lazy;
+import org.springframework.stereotype.Component;
+
+/**
+ * This is the converter from/to the Item in the DSpace API data model and the
+ * REST data model
+ *
+ * @author Andrea Bollini (andrea.bollini at 4science.it)
+ */
+@Component
+public class FilteredItemConverter {
+
+    // Must be loaded @Lazy, as ConverterService autowires all DSpaceConverter components
+    @Lazy
+    @Autowired
+    ConverterService converter;
+    @Autowired
+    private ItemService itemService;
+    @Autowired
+    private CollectionConverter collectionConverter;
+    @Autowired
+    AuthorizeService authorizeService;
+    @Autowired
+    MetadataExposureService metadataExposureService;
+
+    private static final Logger log = org.apache.logging.log4j.LogManager.getLogger(FilteredItemConverter.class);
+
+    public FilteredItemRest convert(Item obj, Projection projection) {
+        FilteredItemRest item = new FilteredItemRest();
+
+        item.setHandle(obj.getHandle());
+        if (obj.getID() != null) {
+            item.setUuid(obj.getID().toString());
+        }
+        item.setName(obj.getName());
+
+        MetadataValueList metadataValues = getPermissionFilteredMetadata(
+                ContextUtil.obtainCurrentRequestContext(), obj);
+        item.setMetadata(converter.toRest(metadataValues, projection));
+
+        item.setInArchive(obj.isArchived());
+        item.setDiscoverable(obj.isDiscoverable());
+        item.setWithdrawn(obj.isWithdrawn());
+        item.setLastModified(obj.getLastModified());
+
+        List<MetadataValue> entityTypes =
+                itemService.getMetadata(obj, "dspace", "entity", "type", Item.ANY, false);
+        if (CollectionUtils.isNotEmpty(entityTypes) && StringUtils.isNotBlank(entityTypes.get(0).getValue())) {
+            item.setEntityType(entityTypes.get(0).getValue());
+        }
+
+        Optional.ofNullable(obj.getOwningCollection())
+            .map(coll -> collectionConverter.convert(coll, Projection.DEFAULT))
+            .ifPresent(item::setOwningCollection);
+
+        return item;
+    }
+
+    /**
+     * Retrieves the metadata list filtered according to the hidden metadata configuration
+     * When the context is null, it will return the metadatalist as for an anonymous user
+     * Overrides the parent method to include virtual metadata
+     * @param context The context
+     * @param obj     The object of which the filtered metadata will be retrieved
+     * @return A list of object metadata (including virtual metadata) filtered based on the hidden metadata
+     * configuration
+     */
+    private MetadataValueList getPermissionFilteredMetadata(Context context, Item obj) {
+        List<MetadataValue> fullList = itemService.getMetadata(obj, Item.ANY, Item.ANY, Item.ANY, Item.ANY, true);
+        List<MetadataValue> returnList = new LinkedList<>();
+        try {
+            if (obj.isWithdrawn() && (Objects.isNull(context) ||
+                                      Objects.isNull(context.getCurrentUser()) || !authorizeService.isAdmin(context))) {
+                return new MetadataValueList(new ArrayList<>());
+            }
+            if (context != null && (authorizeService.isAdmin(context) || itemService.canEdit(context, obj))) {
+                return new MetadataValueList(fullList);
+            }
+            for (MetadataValue mv : fullList) {
+                MetadataField metadataField = mv.getMetadataField();
+                if (!metadataExposureService
+                        .isHidden(context, metadataField.getMetadataSchema().getName(),
+                                  metadataField.getElement(),
+                                  metadataField.getQualifier())) {
+                    returnList.add(mv);
+                }
+            }
+        } catch (SQLException e) {
+            log.error("Error filtering item metadata based on permissions", e);
+        }
+        return new MetadataValueList(returnList);
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/link/contentreport/ContentReportSupportHalLinkFactory.java

@@ -0,0 +1,47 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.link.contentreport;
+
+import java.util.LinkedList;
+
+import org.dspace.app.rest.ContentReportRestController;
+import org.dspace.app.rest.link.HalLinkFactory;
+import org.dspace.app.rest.model.hateoas.ContentReportSupportResource;
+import org.springframework.data.domain.Pageable;
+import org.springframework.hateoas.IanaLinkRelations;
+import org.springframework.hateoas.Link;
+import org.springframework.stereotype.Component;
+
+/**
+ * This class adds the self and report links to the ContentReportSupportResource.
+ * @author Jean-François Morin (Université Laval)
+ */
+@Component
+public class ContentReportSupportHalLinkFactory
+    extends HalLinkFactory<ContentReportSupportResource, ContentReportRestController> {
+
+    @Override
+    protected void addLinks(ContentReportSupportResource halResource, Pageable pageable, LinkedList<Link> list)
+        throws Exception {
+
+        list.add(buildLink(IanaLinkRelations.SELF.value(), getMethodOn().getContentReportSupport()));
+        list.add(buildLink("filteredcollections", getMethodOn().getFilteredCollections(null, null, null)));
+        list.add(buildLink("filtereditems", getMethodOn()
+                .getFilteredItems(null, null, null, null, null, null, null, null, null)));
+    }
+
+    @Override
+    protected Class<ContentReportRestController> getControllerClass() {
+        return ContentReportRestController.class;
+    }
+
+    @Override
+    protected Class<ContentReportSupportResource> getResourceClass() {
+        return ContentReportSupportResource.class;
+    }
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/ContentReportSupportRest.java

@@ -0,0 +1,38 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import org.dspace.app.rest.ContentReportRestController;
+
+public class ContentReportSupportRest extends BaseObjectRest<String> {
+
+    private static final long serialVersionUID = 9137258312781361906L;
+    public static final String NAME = "contentreport";
+    public static final String CATEGORY = RestModel.CONTENT_REPORT;
+
+    @Override
+    public String getCategory() {
+        return CATEGORY;
+    }
+
+    @Override
+    public Class<?> getController() {
+        return ContentReportRestController.class;
+    }
+
+    @Override
+    public String getType() {
+        return NAME;
+    }
+
+    @Override
+    public String getTypePlural() {
+        return NAME;
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/FilteredCollectionRest.java

@@ -0,0 +1,104 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import java.util.EnumMap;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Optional;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import org.dspace.contentreport.Filter;
+import org.dspace.contentreport.FilteredCollection;
+
+/**
+ * This class serves as a REST representation of a single Collection in a {@link FilteredCollectionsRest}
+ * from the DSpace statistics. It takes its values from a @link FilteredCollection} instance.
+ * It must not extend BaseObjectRest<?>.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredCollectionRest {
+
+    public static final String NAME = "filtered-collection";
+    public static final String CATEGORY = RestModel.CONTENT_REPORT;
+
+    /** Name of the collection */
+    private String label;
+    /** Handle of the collection, used to make it clickable from the generated report */
+    private String handle;
+    /** Name of the owning community */
+    @JsonProperty("community_label")
+    private String communityLabel;
+    /** Handle of the owning community, used to make it clickable from the generated report */
+    @JsonProperty("community_handle")
+    private String communityHandle;
+    /** Total number of items in the collection */
+    @JsonProperty("nb_total_items")
+    private int totalItems;
+    /** Number of filtered items per requested filter in the collection */
+    private Map<Filter, Integer> values = new EnumMap<>(Filter.class);
+    /** Number of items in the collection that match all requested filters */
+    @JsonProperty("all_filters_value")
+    private int allFiltersValue;
+
+    /**
+     * Builds a FilteredCollectionRest instance from a {@link FilteredCollection} instance.
+     * @param model the FilteredCollection instance that provides values to the
+     * FilteredCollectionRest instance to be created
+     * @return a FilteredCollectionRest instance built from the provided model object
+     */
+    public static FilteredCollectionRest of(FilteredCollection model) {
+        Objects.requireNonNull(model);
+
+        var coll = new FilteredCollectionRest();
+        coll.label = model.getLabel();
+        coll.handle = model.getHandle();
+        coll.communityLabel = model.getCommunityLabel();
+        coll.communityHandle = model.getCommunityHandle();
+        coll.totalItems = model.getTotalItems();
+        coll.allFiltersValue = model.getAllFiltersValue();
+        Optional.ofNullable(model.getValues()).ifPresent(coll.values::putAll);
+
+        return coll;
+    }
+
+    @JsonProperty(access = JsonProperty.Access.READ_ONLY)
+    public String getType() {
+        return NAME;
+    }
+
+    public Map<Filter, Integer> getValues() {
+        return values;
+    }
+
+    public String getLabel() {
+        return label;
+    }
+
+    public String getHandle() {
+        return handle;
+    }
+
+    public String getCommunityLabel() {
+        return communityLabel;
+    }
+
+    public String getCommunityHandle() {
+        return communityHandle;
+    }
+
+    public int getTotalItems() {
+        return totalItems;
+    }
+
+    public int getAllFiltersValue() {
+        return allFiltersValue;
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/FilteredCollectionsQuery.java

@@ -0,0 +1,54 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import java.util.Collection;
+import java.util.EnumSet;
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import org.dspace.contentreport.Filter;
+
+/**
+ * Structured query contents for the Filtered Collections report
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredCollectionsQuery {
+
+    private Set<Filter> filters = EnumSet.noneOf(Filter.class);
+
+    /**
+     * Shortcut method that builds a FilteredCollectionsQuery instance
+     * from its building blocks.
+     * @param filters filters to apply to existing items.
+     * The filters mapping to true will be applied, others (either missing or
+     * mapping to false) will not.
+     * @return a FilteredCollectionsQuery instance built from the provided parameters
+     */
+    public static FilteredCollectionsQuery of(Collection<Filter> filters) {
+        var query = new FilteredCollectionsQuery();
+        Optional.ofNullable(filters).ifPresent(query.filters::addAll);
+        return query;
+    }
+
+    public Set<Filter> getFilters() {
+        return filters;
+    }
+
+    public void setFilters(Set<Filter> filters) {
+        this.filters = filters;
+    }
+
+    public String toQueryString() {
+        return filters.stream()
+                .map(f -> "filters=" + f.getId())
+                .collect(Collectors.joining("&"));
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/FilteredCollectionsRest.java

@@ -0,0 +1,82 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+import org.dspace.app.rest.ContentReportRestController;
+import org.dspace.contentreport.FilteredCollections;
+
+/**
+ * This class serves as a REST representation of a Filtered Collections Report.
+ * The name must match that of the associated resource class (FilteredCollectionsResource) except for
+ * the suffix. This is why it is not named something like FilteredCollectionsReportRest.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredCollectionsRest extends BaseObjectRest<String> {
+
+    private static final long serialVersionUID = -1109226348211060786L;
+    /** Type of instances of this class, used by the DSpace REST infrastructure */
+    public static final String NAME = "filteredcollectionsreport";
+    /** Category of instances of this class, used by the DSpace REST infrastructure */
+    public static final String CATEGORY = RestModel.CONTENT_REPORT;
+
+    /** Collections included in the report */
+    private List<FilteredCollectionRest> collections = new ArrayList<>();
+    /** Report summary */
+    private FilteredCollectionRest summary;
+
+    /**
+     * Builds a FilteredCollectionsRest instance from a {@link FilteredCollections} instance.
+     * Each underlying FilteredCollection is converted to a FilteredCollectionRest instance.
+     * @param model the FilteredCollections instance that provides values to the
+     * FilteredCollectionsRest instance to be created
+     * @return a FilteredCollectionsRest instance built from the provided model object
+     */
+    public static FilteredCollectionsRest of(FilteredCollections model) {
+        var colls = new FilteredCollectionsRest();
+        Optional.ofNullable(model.getCollections()).ifPresent(cs ->
+                cs.stream()
+                        .map(FilteredCollectionRest::of)
+                        .forEach(colls.collections::add));
+        colls.summary = FilteredCollectionRest.of(model.getSummary());
+        return colls;
+    }
+
+    @Override
+    public String getCategory() {
+        return CATEGORY;
+    }
+
+    @Override
+    public Class<?> getController() {
+        return ContentReportRestController.class;
+    }
+
+    @Override
+    public String getType() {
+        return NAME;
+    }
+
+    @Override
+    public String getTypePlural() {
+        return getType();
+    }
+
+    public List<FilteredCollectionRest> getCollections() {
+        return collections;
+    }
+
+    public FilteredCollectionRest getSummary() {
+        return summary;
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/FilteredItemRest.java

@@ -0,0 +1,128 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import java.util.Date;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+/**
+ * Specialization of ItemRest dedicated to the Filtered Items report.
+ * This class adds the owning collection property required to properly
+ * display search results without compromising the expected behaviour
+ * of standard ItemRest instances, in all other contexts, especially
+ * when it comes to embedded contents, a criterion that is widely checked
+ * against in several integration tests.
+ *
+ * @author Jean-François Morin (jean-francois.morin@bibl.ulaval.ca)
+ */
+public class FilteredItemRest {
+
+    public static final String NAME = "filtered-item";
+    public static final String CATEGORY = RestAddressableModel.CONTENT_REPORT;
+
+    public static final String OWNING_COLLECTION = "owningCollection";
+
+    private String uuid;
+    private String name;
+    private String handle;
+    MetadataRest metadata = new MetadataRest();
+    private boolean inArchive = false;
+    private boolean discoverable = false;
+    private boolean withdrawn = false;
+    private Date lastModified = new Date();
+    @JsonProperty(access = JsonProperty.Access.READ_ONLY)
+    private String entityType = null;
+    private CollectionRest owningCollection;
+
+    @JsonProperty(access = JsonProperty.Access.READ_ONLY)
+    public String getType() {
+        return NAME;
+    }
+
+    public String getUuid() {
+        return uuid;
+    }
+
+    public void setUuid(String uuid) {
+        this.uuid = uuid;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getHandle() {
+        return handle;
+    }
+
+    public void setHandle(String handle) {
+        this.handle = handle;
+    }
+
+    public MetadataRest getMetadata() {
+        return metadata;
+    }
+
+    public void setMetadata(MetadataRest metadata) {
+        this.metadata = metadata;
+    }
+
+    public boolean getInArchive() {
+        return inArchive;
+    }
+
+    public void setInArchive(boolean inArchive) {
+        this.inArchive = inArchive;
+    }
+
+    public boolean getDiscoverable() {
+        return discoverable;
+    }
+
+    public void setDiscoverable(boolean discoverable) {
+        this.discoverable = discoverable;
+    }
+
+    public boolean getWithdrawn() {
+        return withdrawn;
+    }
+
+    public void setWithdrawn(boolean withdrawn) {
+        this.withdrawn = withdrawn;
+    }
+
+    public Date getLastModified() {
+        return lastModified;
+    }
+
+    public void setLastModified(Date lastModified) {
+        this.lastModified = lastModified;
+    }
+
+    public String getEntityType() {
+        return entityType;
+    }
+
+    public void setEntityType(String entityType) {
+        this.entityType = entityType;
+    }
+
+    public CollectionRest getOwningCollection() {
+        return owningCollection;
+    }
+
+    public void setOwningCollection(CollectionRest owningCollection) {
+        this.owningCollection = owningCollection;
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/FilteredItemsQueryPredicate.java

@@ -0,0 +1,74 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import java.util.Optional;
+
+import org.apache.commons.lang3.StringUtils;
+import org.dspace.contentreport.QueryOperator;
+
+/**
+ * Data structure representing a query predicate used by the Filtered Items report
+ * to filter items to retrieve. This version is specific to the REST layer and its
+ * property types are detached from the persistence layer.
+ * @see org.dspace.contentreport.QueryPredicate
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredItemsQueryPredicate {
+
+    private String field;
+    private QueryOperator operator;
+    private String value;
+
+    /**
+     * Shortcut method that builds a FilteredItemsQueryPredicate from a single field, an operator, and a value.
+     * @param field Predicate subject
+     * @param operator Predicate operator
+     * @param value Predicate object
+     * @return a FilteredItemsQueryPredicate instance built from the provided parameters
+     */
+    public static FilteredItemsQueryPredicate of(String field, QueryOperator operator, String value) {
+        var predicate = new FilteredItemsQueryPredicate();
+        predicate.field = field;
+        predicate.operator = operator;
+        predicate.value = value;
+        return predicate;
+    }
+
+    /**
+     * Shortcut method that builds a FilteredItemsQueryPredicate from a colon-separated string value.
+     * @param value Colon-separated string value (field:operator:object or field:operator)
+     * @return a FilteredItemsQueryPredicate instance built from the provided value
+     */
+    public static FilteredItemsQueryPredicate of(String value) {
+        String[] tokens = value.split("\\:");
+        String field = tokens.length > 0 ? tokens[0].trim() : "";
+        QueryOperator operator = tokens.length > 1 ? QueryOperator.get(tokens[1].trim()) : null;
+        String object = tokens.length > 2 ? StringUtils.trimToEmpty(tokens[2]) : "";
+        return of(field, operator, object);
+    }
+
+    public String getField() {
+        return field;
+    }
+
+    public QueryOperator getOperator() {
+        return operator;
+    }
+
+    public String getValue() {
+        return value;
+    }
+
+    @Override
+    public String toString() {
+        String op = Optional.ofNullable(operator).map(QueryOperator::getCode).orElse("");
+        return field + ":" + op + ":" + value;
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/FilteredItemsQueryRest.java

@@ -0,0 +1,148 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.List;
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import org.apache.commons.lang3.StringUtils;
+import org.dspace.contentreport.Filter;
+import org.dspace.contentreport.QueryOperator;
+
+/**
+ * REST-based version of structured query contents for the Filtered Items report
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredItemsQueryRest {
+
+    private List<String> collections = new ArrayList<>();
+    private List<FilteredItemsQueryPredicate> queryPredicates = new ArrayList<>();
+    private int pageLimit;
+    private Set<Filter> filters = EnumSet.noneOf(Filter.class);
+    private List<String> additionalFields = new ArrayList<>();
+
+    /**
+     * Shortcut method that builds a FilteredItemsQueryRest instance
+     * from its building blocks.
+     * @param collectionUuids collection UUIDs to add
+     * @param predicates query predicates used to filter existing items
+     * @param pageLimit number of items per page
+     * @param filters filters to apply to existing items
+     * The filters mapping to true will be applied, others (either missing or
+     * mapping to false) will not.
+     * @param additionalFields additional fields to display in the resulting report
+     * @return a FilteredItemsQueryRest instance built from the provided parameters
+     */
+    public static FilteredItemsQueryRest of(Collection<String> collectionUuids,
+            Collection<FilteredItemsQueryPredicate> predicates, int pageLimit,
+            Collection<Filter> filters, Collection<String> additionalFields) {
+        var query = new FilteredItemsQueryRest();
+        Optional.ofNullable(collectionUuids).ifPresent(query.collections::addAll);
+        Optional.ofNullable(predicates).ifPresent(query.queryPredicates::addAll);
+        query.pageLimit = pageLimit;
+        Optional.ofNullable(filters).ifPresent(query.filters::addAll);
+        Optional.ofNullable(additionalFields).ifPresent(query.additionalFields::addAll);
+        return query;
+    }
+
+    public List<String> getCollections() {
+        return collections;
+    }
+
+    public void setCollections(List<String> collections) {
+        this.collections = collections;
+    }
+
+    public List<FilteredItemsQueryPredicate> getQueryPredicates() {
+        return queryPredicates;
+    }
+
+    public void setQueryPredicates(List<FilteredItemsQueryPredicate> queryPredicates) {
+        this.queryPredicates = queryPredicates;
+    }
+
+    public List<String> getPredicateFields() {
+        if (queryPredicates == null) {
+            return Collections.emptyList();
+        }
+        return queryPredicates.stream()
+                .map(FilteredItemsQueryPredicate::getField)
+                .collect(Collectors.toList());
+    }
+
+    public List<QueryOperator> getPredicateOperators() {
+        if (queryPredicates == null) {
+            return Collections.emptyList();
+        }
+        return queryPredicates.stream()
+                .map(FilteredItemsQueryPredicate::getOperator)
+                .collect(Collectors.toList());
+    }
+
+    public List<String> getPredicateValues() {
+        if (queryPredicates == null) {
+            return Collections.emptyList();
+        }
+        return queryPredicates.stream()
+                .map(FilteredItemsQueryPredicate::getValue)
+                .map(s -> s == null ? "" : s)
+                .collect(Collectors.toList());
+    }
+
+    public int getPageLimit() {
+        return pageLimit;
+    }
+
+    public void setPageLimit(int pageLimit) {
+        this.pageLimit = pageLimit;
+    }
+
+    public Set<Filter> getFilters() {
+        return filters;
+    }
+
+    public void setFilters(Set<Filter> filters) {
+        this.filters = filters;
+    }
+
+    public List<String> getAdditionalFields() {
+        return additionalFields;
+    }
+
+    public void setAdditionalFields(List<String> additionalFields) {
+        this.additionalFields = additionalFields;
+    }
+
+    public String toQueryString() {
+        String colls = collections.stream()
+                .map(coll -> "collection=" + coll)
+                .collect(Collectors.joining("&"));
+        String preds = queryPredicates.stream()
+                .map(pred -> "queryPredicates=" + pred)
+                .collect(Collectors.joining("&"));
+        String pgLimit = "pageLimit=" + pageLimit;
+        String fltrs = filters.stream()
+                .map(e -> "filters=" + e.getId())
+                .collect(Collectors.joining("&"));
+        String flds = additionalFields.stream()
+                .map(fld -> "additionalFields=" + fld)
+                .collect(Collectors.joining("&"));
+
+        return Stream.of(colls, preds, pgLimit, fltrs, flds)
+                .filter(StringUtils::isNotBlank)
+                .collect(Collectors.joining("&"));
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/FilteredItemsRest.java

@@ -0,0 +1,88 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.dspace.app.rest.ContentReportRestController;
+
+/**
+ * This class serves as a REST representation of a Filtered Items Report.
+ * The name must match that of the associated resource class (FilteredItemsResource) except for
+ * the suffix. This is why it is not named something like FilteredItemsReportRest.
+ *
+ * @author Jean-François Morin (Université Laval)
+ */
+public class FilteredItemsRest extends BaseObjectRest<String> {
+
+    private static final long serialVersionUID = -2483812920345013458L;
+    /** Type of instances of this class, used by the DSpace REST infrastructure */
+    public static final String NAME = "filtereditemsreport";
+    /** Category of instances of this class, used by the DSpace REST infrastructure */
+    public static final String CATEGORY = RestModel.CONTENT_REPORT;
+
+    /** Items included in the report */
+    private List<FilteredItemRest> items = new ArrayList<>();
+    /** Total item count (for pagination) */
+    private long itemCount;
+
+    /**
+     * Builds a FilteredItemsRest instance from a list of items and an total item count.
+     * To avoid adding a dependency to any Spring-managed service here, the items
+     * provided here are already converted to FilteredItemRest instances.
+     * @param items the items to add to the FilteredItemsRest instance to be created
+     * @param itemCount total number of items found regardless of any pagination constraint
+     * @return a FilteredItemsRest instance built from the provided data
+     */
+    public static FilteredItemsRest of(List<FilteredItemRest> items, long itemCount) {
+        var itemsRest = new FilteredItemsRest();
+        itemsRest.items.addAll(items);
+        itemsRest.itemCount = itemCount;
+        return itemsRest;
+    }
+
+    @Override
+    public String getCategory() {
+        return CATEGORY;
+    }
+
+    /**
+     * Return controller class responsible for this Rest object
+     *
+     * @return Controller class responsible for this Rest object
+     */
+    @Override
+    public Class<?> getController() {
+        return ContentReportRestController.class;
+    }
+
+    @Override
+    public String getType() {
+        return NAME;
+    }
+
+    @Override
+    public String getTypePlural() {
+        return getType();
+    }
+
+    /**
+     * Returns a defensive copy of the items included in this report.
+     *
+     * @return the items included in this report
+     */
+    public List<FilteredItemRest> getItems() {
+        return new ArrayList<>(items);
+    }
+
+    public long getItemCount() {
+        return itemCount;
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/RestModel.java

@@ -20,6 +20,7 @@ import com.fasterxml.jackson.annotation.JsonIgnore;
 public interface RestModel extends Serializable {
 
     public static final String ROOT = "root";
+    public static final String CONTENT_REPORT = "contentreport";
     public static final String CORE = "core";
     public static final String EPERSON = "eperson";
     public static final String DISCOVER = "discover";

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/hateoas/ContentReportSupportResource.java

@@ -0,0 +1,18 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model.hateoas;
+
+import org.dspace.app.rest.model.ContentReportSupportRest;
+import org.dspace.app.rest.model.hateoas.annotations.RelNameDSpaceResource;
+
+@RelNameDSpaceResource(ContentReportSupportRest.NAME)
+public class ContentReportSupportResource extends HALResource<ContentReportSupportRest> {
+    public ContentReportSupportResource(ContentReportSupportRest content) {
+        super(content);
+    }
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/hateoas/FilteredCollectionsResource.java

@@ -0,0 +1,21 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model.hateoas;
+
+import org.dspace.app.rest.model.FilteredCollectionsRest;
+import org.dspace.app.rest.model.hateoas.annotations.RelNameDSpaceResource;
+import org.dspace.app.rest.utils.Utils;
+
+@RelNameDSpaceResource(FilteredCollectionsRest.NAME)
+public class FilteredCollectionsResource extends DSpaceResource<FilteredCollectionsRest> {
+
+    public FilteredCollectionsResource(FilteredCollectionsRest data, Utils utils) {
+        super(data, utils);
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/model/hateoas/FilteredItemsResource.java

@@ -0,0 +1,21 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.model.hateoas;
+
+import org.dspace.app.rest.model.FilteredItemsRest;
+import org.dspace.app.rest.model.hateoas.annotations.RelNameDSpaceResource;
+import org.dspace.app.rest.utils.Utils;
+
+@RelNameDSpaceResource(FilteredItemsRest.NAME)
+public class FilteredItemsResource extends DSpaceResource<FilteredItemsRest> {
+
+    public FilteredItemsResource(FilteredItemsRest data, Utils utils) {
+        super(data, utils);
+    }
+
+}

dspace-server-webapp/src/main/java/org/dspace/app/rest/repository/ContentReportRestRepository.java

@@ -0,0 +1,97 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.repository;
+
+import java.sql.SQLException;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import org.dspace.app.rest.converter.FilteredItemConverter;
+import org.dspace.app.rest.model.ContentReportSupportRest;
+import org.dspace.app.rest.model.FilteredCollectionsQuery;
+import org.dspace.app.rest.model.FilteredCollectionsRest;
+import org.dspace.app.rest.model.FilteredItemRest;
+import org.dspace.app.rest.model.FilteredItemsQueryPredicate;
+import org.dspace.app.rest.model.FilteredItemsQueryRest;
+import org.dspace.app.rest.model.FilteredItemsRest;
+import org.dspace.app.rest.projection.Projection;
+import org.dspace.content.MetadataField;
+import org.dspace.contentreport.Filter;
+import org.dspace.contentreport.FilteredCollection;
+import org.dspace.contentreport.FilteredCollections;
+import org.dspace.contentreport.FilteredItems;
+import org.dspace.contentreport.FilteredItemsQuery;
+import org.dspace.contentreport.QueryPredicate;
+import org.dspace.contentreport.service.ContentReportService;
+import org.dspace.core.Context;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.domain.Pageable;
+import org.springframework.stereotype.Component;
+
+/**
+ * This repository serves the content reports ported from DSpace 6.x
+ * (Filtered Collections and Filtered Items).
+ * @author Jean-François Morin (Université Laval)
+ */
+@Component(ContentReportSupportRest.CATEGORY + "." + ContentReportSupportRest.NAME)
+public class ContentReportRestRepository extends AbstractDSpaceRestRepository {
+
+    @Autowired
+    private ContentReportService contentReportService;
+    @Autowired
+    private FilteredItemConverter itemConverter;
+
+    public ContentReportSupportRest getContentReportSupport() {
+        return new ContentReportSupportRest();
+    }
+
+    public FilteredCollectionsRest findFilteredCollections(Context context, FilteredCollectionsQuery query) {
+        Set<Filter> filters = query.getFilters();
+
+        List<FilteredCollection> colls = contentReportService.findFilteredCollections(context, filters);
+        FilteredCollections report = FilteredCollections.of(colls);
+
+        FilteredCollectionsRest reportRest = FilteredCollectionsRest.of(report);
+        reportRest.setId("filteredcollections");
+        return reportRest;
+    }
+
+    public FilteredItemsRest findFilteredItems(Context context, FilteredItemsQueryRest queryRest, Pageable pageable) {
+        List<QueryPredicate> predicates = queryRest.getQueryPredicates().stream()
+                .map(pred -> convertPredicate(context, pred))
+                .collect(Collectors.toList());
+        FilteredItemsQuery query = new FilteredItemsQuery();
+        query.setCollections(queryRest.getCollections());
+        query.setQueryPredicates(predicates);
+        query.setFilters(queryRest.getFilters());
+        query.setAdditionalFields(queryRest.getAdditionalFields());
+        query.setOffset(pageable.getOffset());
+        query.setPageLimit(pageable.getPageSize());
+
+        FilteredItems items = contentReportService.findFilteredItems(context, query);
+
+        List<FilteredItemRest> filteredItemsRest = items.getItems().stream()
+                .map(item -> itemConverter.convert(item, Projection.DEFAULT))
+                .collect(Collectors.toList());
+        FilteredItemsRest report = FilteredItemsRest.of(filteredItemsRest, items.getItemCount());
+        report.setId("filtereditems");
+
+        return report;
+    }
+
+    private QueryPredicate convertPredicate(Context context, FilteredItemsQueryPredicate predicate) {
+        try {
+            List<MetadataField> fields = contentReportService.getMetadataFields(context, predicate.getField());
+            return QueryPredicate.of(fields, predicate.getOperator(), predicate.getValue());
+        } catch (SQLException e) {
+            throw new IllegalArgumentException(e.getMessage(), e);
+        }
+    }
+
+}

dspace-server-webapp/src/test/java/org/dspace/app/rest/ContentReportRestRepositoryIT.java

@@ -0,0 +1,263 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest;
+
+import static com.jayway.jsonpath.matchers.JsonPathMatchers.hasJsonPath;
+import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.dspace.app.rest.matcher.ContentReportMatcher;
+import org.dspace.app.rest.matcher.HalMatcher;
+import org.dspace.app.rest.model.FilteredCollectionsQuery;
+import org.dspace.app.rest.model.FilteredItemsQueryPredicate;
+import org.dspace.app.rest.model.FilteredItemsQueryRest;
+import org.dspace.app.rest.test.AbstractControllerIntegrationTest;
+import org.dspace.builder.CollectionBuilder;
+import org.dspace.builder.CommunityBuilder;
+import org.dspace.builder.ItemBuilder;
+import org.dspace.content.Collection;
+import org.dspace.content.Item;
+import org.dspace.contentreport.Filter;
+import org.dspace.contentreport.FilteredCollection;
+import org.dspace.contentreport.QueryOperator;
+import org.dspace.services.ConfigurationService;
+import org.hamcrest.Matcher;
+import org.hamcrest.Matchers;
+import org.junit.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+
+/**
+ * Integration tests for the content reports ported from DSpace 6.x
+ * (Filtered Collections and Filtered Items).
+ * @author Jean-François Morin (Université Laval)
+ */
+public class ContentReportRestRepositoryIT extends AbstractControllerIntegrationTest {
+
+    @Autowired
+    private ConfigurationService configurationService;
+
+    @Test
+    public void testFilteredCollections() throws Exception {
+        context.turnOffAuthorisationSystem();
+
+        configurationService.setProperty("contentreport.enable", Boolean.TRUE);
+
+        TestKit testKit = setupCollectionsAndItems();
+        Collection col1 = testKit.collections.get(0);
+        Collection col2 = testKit.collections.get(1);
+
+        context.restoreAuthSystemState();
+        String token = getAuthToken(admin.getEmail(), password);
+
+        Map<Filter, Integer> valuesCol1 = Map.of(Filter.IS_DISCOVERABLE, 1);
+        FilteredCollection fcol1 = FilteredCollection.of(col1.getName(), col1.getHandle(),
+                parentCommunity.getName(), parentCommunity.getHandle(),
+                1, 1, valuesCol1, true);
+        Map<Filter, Integer> valuesCol2 = Map.of(Filter.IS_DISCOVERABLE, 2);
+        FilteredCollection fcol2 = FilteredCollection.of(col2.getName(), col2.getHandle(),
+                parentCommunity.getName(), parentCommunity.getHandle(),
+                2, 2, valuesCol2, true);
+
+        FilteredCollectionsQuery query = FilteredCollectionsQuery.of(Set.of(Filter.IS_DISCOVERABLE));
+
+        getClient(token).perform(get("/api/contentreport/filteredcollections?" + query.toQueryString()))
+                   .andExpect(status().isOk())
+                   .andExpect(jsonPath("$.collections", Matchers.containsInAnyOrder(
+                           ContentReportMatcher.matchFilteredCollectionProperties(fcol1),
+                           ContentReportMatcher.matchFilteredCollectionProperties(fcol2)
+                   )))
+                   .andExpect(jsonPath("type", is("filteredcollectionsreport")))
+                   .andExpect(jsonPath("$.summary",
+                           ContentReportMatcher.matchFilteredCollectionSummary(3, 3)))
+                   .andExpect(jsonPath("$._links.self.href",
+                           Matchers.containsString("/api/contentreport/filteredcollections")));
+    }
+
+    @Test
+    public void testFilteredCollectionsUnauthorized() throws Exception {
+        context.turnOffAuthorisationSystem();
+
+        configurationService.setProperty("contentreport.enable", Boolean.TRUE);
+
+        setupCollectionsAndItems();
+
+        context.restoreAuthSystemState();
+
+        FilteredCollectionsQuery query = FilteredCollectionsQuery.of(Set.of(Filter.IS_DISCOVERABLE));
+
+        getClient().perform(get("/api/contentreport/filteredcollections?" + query.toQueryString()))
+                .andExpect(status().isUnauthorized());
+    }
+
+    @Test
+    public void testFilteredCollectionsOff() throws Exception {
+        context.turnOffAuthorisationSystem();
+
+        configurationService.setProperty("contentreport.enable", Boolean.FALSE);
+
+        setupCollectionsAndItems();
+
+        context.restoreAuthSystemState();
+        String token = getAuthToken(admin.getEmail(), password);
+
+        FilteredCollectionsQuery query = FilteredCollectionsQuery.of(Set.of(Filter.IS_DISCOVERABLE));
+
+        getClient(token).perform(get("/api/contentreport/filteredcollections?" + query.toQueryString()))
+                   .andExpect(status().isNotFound());
+    }
+
+    @Test
+    public void testFilteredItems() throws Exception {
+        context.turnOffAuthorisationSystem();
+
+        configurationService.setProperty("contentreport.enable", Boolean.TRUE);
+
+        TestKit testKit = setupCollectionsAndItems();
+        Item publicItem2 = testKit.items.get(1);
+        Item publicItem3 = testKit.items.get(2);
+
+        context.restoreAuthSystemState();
+        String token = getAuthToken(admin.getEmail(), password);
+
+        FilteredItemsQueryRest query = FilteredItemsQueryRest.of(null,
+                List.of(FilteredItemsQueryPredicate.of("dc.contributor.author", QueryOperator.EQUALS, "Doe, Jane")),
+                100, null, List.of("dc.subject"));
+
+        getClient(token).perform(get("/api/contentreport/filtereditems?" + query.toQueryString()))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$", HalMatcher.matchNoEmbeds()))
+                .andExpect(jsonPath("$.itemCount", is(2)))
+                .andExpect(jsonPath("$.items", Matchers.containsInAnyOrder(
+                        matchItemProperties(publicItem2),
+                        matchItemProperties(publicItem3)
+                )));
+    }
+
+    @Test
+    public void testFilteredItemsUnauthorized() throws Exception {
+        context.turnOffAuthorisationSystem();
+
+        configurationService.setProperty("contentreport.enable", Boolean.TRUE);
+
+        setupCollectionsAndItems();
+
+        context.restoreAuthSystemState();
+
+        FilteredItemsQueryRest query = FilteredItemsQueryRest.of(null,
+                List.of(FilteredItemsQueryPredicate.of("dc.contributor.author", QueryOperator.EQUALS, "Doe, Jane")),
+                100, null, List.of("dc.subject"));
+
+        getClient().perform(get("/api/contentreport/filtereditems?" + query.toQueryString()))
+                .andExpect(status().isUnauthorized());
+    }
+
+    @Test
+    public void testFilteredItemsOff() throws Exception {
+        context.turnOffAuthorisationSystem();
+
+        configurationService.setProperty("contentreport.enable", Boolean.FALSE);
+
+        setupCollectionsAndItems();
+
+        context.restoreAuthSystemState();
+        String token = getAuthToken(admin.getEmail(), password);
+
+        FilteredItemsQueryRest query = FilteredItemsQueryRest.of(null,
+                List.of(FilteredItemsQueryPredicate.of("dc.contributor.author", QueryOperator.EQUALS, "Doe, Jane")),
+                100, null, List.of("dc.subject"));
+
+        getClient(token).perform(get("/api/contentreport/filtereditems?" + query.toQueryString()))
+                .andExpect(status().isNotFound());
+    }
+
+    // Need for a specific filtered item type...
+    private static Matcher<? super Object> matchItemProperties(Item item) {
+        return allOf(
+            hasJsonPath("$.uuid", is(item.getID().toString())),
+            hasJsonPath("$.name", is(item.getName())),
+            hasJsonPath("$.handle", is(item.getHandle())),
+            hasJsonPath("$.inArchive", is(item.isArchived())),
+            hasJsonPath("$.discoverable", is(item.isDiscoverable())),
+            hasJsonPath("$.withdrawn", is(item.isWithdrawn())),
+            hasJsonPath("$.lastModified", is(notNullValue())),
+            hasJsonPath("$.type", is("filtered-item"))
+        );
+    }
+
+    private TestKit setupCollectionsAndItems() {
+        //** GIVEN **
+        //1. A community with two collections.
+        parentCommunity = CommunityBuilder.createCommunity(context)
+                .withName("My Community")
+                .build();
+
+        Collection col1 = CollectionBuilder.createCollection(context, parentCommunity).withName("Collection 1").build();
+        Collection col2 = CollectionBuilder.createCollection(context, parentCommunity).withName("Collection 2").build();
+
+        LocalDate today = LocalDate.now();
+        LocalDate pastDate = today.minusDays(10);
+        String fmtPastDate = DateTimeFormatter.ISO_DATE.format(pastDate);
+        LocalDate futureDate = today.plusDays(10);
+        String fmtFutureDate = DateTimeFormatter.ISO_DATE.format(futureDate);
+
+        //2. Three items, two of which are available and discoverable...
+        Item item1 = ItemBuilder.createItem(context, col1)
+                .withTitle("Public item 1")
+                .withIssueDate(fmtPastDate)
+                .withAuthor("Smith, Donald").withAuthor("Doe, John")
+                .withSubject("ExtraEntry")
+                .build();
+
+        Item item2 = ItemBuilder.createItem(context, col2)
+                .withTitle("Public item 2")
+                .withIssueDate(fmtPastDate)
+                .withAuthor("Smith, Maria").withAuthor("Doe, Jane")
+                .withSubject("TestingForMore").withSubject("ExtraEntry")
+                .build();
+
+        // ... and one will be available in a few days.
+        Item item3 = ItemBuilder.createItem(context, col2)
+                .withTitle("Public item 3")
+                .withIssueDate(fmtFutureDate)
+                .withAuthor("Smith, Maria").withAuthor("Doe, Jane")
+                .withSubject("AnotherTest").withSubject("TestingForMore")
+                .withSubject("ExtraEntry")
+                .build();
+
+        TestKit kit = new TestKit();
+        kit.collections.add(col1);
+        kit.collections.add(col2);
+        kit.items.add(item1);
+        kit.items.add(item2);
+        kit.items.add(item3);
+        return kit;
+    }
+
+    /**
+     * Data structure to help trace back the created collections and items to perform the tests.
+     * In a future version (Java 17 or later), this class could be turned into a record.
+     */
+    private static class TestKit {
+
+        public final List<Collection> collections = new ArrayList<>();
+        public final List<Item> items = new ArrayList<>();
+
+    }
+
+}

dspace-server-webapp/src/test/java/org/dspace/app/rest/matcher/ContentReportMatcher.java

@@ -0,0 +1,52 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.rest.matcher;
+
+import static com.jayway.jsonpath.matchers.JsonPathMatchers.hasJsonPath;
+import static org.hamcrest.Matchers.allOf;
+import static org.hamcrest.Matchers.is;
+
+import org.dspace.content.Item;
+import org.dspace.contentreport.FilteredCollection;
+import org.hamcrest.Matcher;
+
+/**
+ * Utility class to construct a Matcher for a FilteredCollectionRest.
+ * @author Jean-François Morin (Université Laval)
+ */
+public class ContentReportMatcher {
+
+    private ContentReportMatcher() { }
+
+    public static Matcher<? super Object> matchFilteredCollectionProperties(FilteredCollection collection) {
+        return allOf(
+                hasJsonPath("$.label", is(collection.getLabel())),
+                hasJsonPath("$.community_label", is(collection.getCommunityLabel())),
+                hasJsonPath("$.community_handle", is(collection.getCommunityHandle())),
+                hasJsonPath("$.nb_total_items", is(collection.getTotalItems())),
+                hasJsonPath("$.all_filters_value", is(collection.getAllFiltersValue()))
+            );
+    }
+
+    public static Matcher<? super Object> matchFilteredCollectionSummary(int nbTotalItems, int nbFilteredItems) {
+        return allOf(
+                hasJsonPath("$.nb_total_items", is(nbTotalItems)),
+                hasJsonPath("$.all_filters_value", is(nbFilteredItems)));
+    }
+
+    public static Matcher<? super Object> matchFilteredItemProperties(Item item) {
+        return allOf(
+                hasJsonPath("$.name", is(item.getName())),
+                hasJsonPath("$.inArchive", is(item.isArchived())),
+                hasJsonPath("$.discoverable", is(item.isDiscoverable())),
+                hasJsonPath("$.withdrawn", is(item.isWithdrawn())),
+                hasJsonPath("$.type", is("item"))
+            );
+    }
+
+}

dspace/config/dspace.cfg

@@ -84,7 +84,7 @@ db.url = jdbc:postgresql://localhost:5432/dspace
 db.driver = org.postgresql.Driver
 
 # PostgreSQL Database Dialect (for Hibernate)
-db.dialect = org.hibernate.dialect.PostgreSQL94Dialect
+db.dialect = org.dspace.util.DSpacePostgreSQLDialect
 
 # Database username and password
 db.username = dspace
@@ -1668,3 +1668,4 @@ include = ${module_dir}/usage-statistics.cfg
 include = ${module_dir}/versioning.cfg
 include = ${module_dir}/workflow.cfg
 include = ${module_dir}/external-providers.cfg
+include = ${module_dir}/contentreport.cfg

dspace/config/local.cfg.EXAMPLE

@@ -76,20 +76,10 @@ dspace.name = DSpace at My University
 # URL for connecting to database
 db.url = jdbc:postgresql://localhost:5432/dspace
 
-# JDBC Driver for PostgreSQL
-db.driver = org.postgresql.Driver
-
-# PostgreSQL Database Dialect (for Hibernate)
-db.dialect = org.hibernate.dialect.PostgreSQL94Dialect
-
 # Database username and password
 db.username = dspace
 db.password = dspace
 
-# Database Schema name
-# For PostgreSQL, this is often "public" (default schema)
-db.schema = public
-
 ## Connection pool parameters
 
 # Maximum number of DB connections in pool (default = 30)
@@ -240,4 +230,4 @@ db.schema = public
 #spring.servlet.multipart.max-file-size = 512MB
 
 # Maximum size of a multipart request (i.e. max total size of all files in one request)
-#spring.servlet.multipart.max-request-size = 512MB
+#spring.servlet.multipart.max-request-size = 512MB

dspace/config/modules/contentreport.cfg

@@ -0,0 +1,10 @@
+#---------------------------------------------------------------#
+#--------------CONTENT REPORTS CONFIGURATIONS-------------------#
+#---------------------------------------------------------------#
+# Used by dspace-server-webapp and the Angular UI               #
+# NOTE: This is currently a beta feature.                       #
+#---------------------------------------------------------------#
+
+# Configuration setting to trigger showing/hiding the Content Reports
+# (REST endpoints on the REST side and menu section on the Angular side)
+#contentreport.enable=true

dspace/config/modules/rest.cfg

@@ -54,4 +54,5 @@ rest.properties.exposed = google.recaptcha.mode
 rest.properties.exposed = cc.license.jurisdiction
 rest.properties.exposed = identifiers.item-status.register-doi
 rest.properties.exposed = authentication-password.domain.valid
-rest.properties.exposed = handle.canonical.prefix
+rest.properties.exposed = handle.canonical.prefix
+rest.properties.exposed = contentreport.enable

dspace/config/spring/api/core-services.xml

@@ -77,6 +77,8 @@
         <constructor-arg name='configPrefix' value='solr'/>
     </bean>
 
+    <bean class="org.dspace.contentreport.ContentReportServiceImpl"/>
+
     <!-- Ensure PluginService is initialized properly via init() method -->
     <bean class="org.dspace.core.LegacyPluginServiceImpl" init-method="init"/>
     <bean class="org.dspace.core.LicenseServiceImpl"/>