DS-1990: Events should contain all identifiers, not only handles.

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

@@ -201,6 +201,9 @@ public class Bundle extends DSpaceObject
         log.info(LogManager.getHeader(context, "create_bundle", "bundle_id="
                 + row.getIntColumn("bundle_id")));
 
+        // if we ever use the identifier service for bundles, we should
+        // create the bundle before we create the Event and should add all 
+        // identifiers to it.
         context.addEvent(new Event(Event.CREATE, Constants.BUNDLE, row.getIntColumn("bundle_id"), null));
 
         return new Bundle(context, row);
@@ -443,7 +446,9 @@ public class Bundle extends DSpaceObject
         // Add the bitstream object
         bitstreams.add(b);
 
-        ourContext.addEvent(new Event(Event.ADD, Constants.BUNDLE, getID(), Constants.BITSTREAM, b.getID(), String.valueOf(b.getSequenceID())));
+        ourContext.addEvent(new Event(Event.ADD, Constants.BUNDLE, getID(), 
+                Constants.BITSTREAM, b.getID(), String.valueOf(b.getSequenceID()),
+                lookupIdentifiers(ourContext)));
 
         // copy authorization policies from bundle to bitstream
         // FIXME: multiple inclusion is affected by this...
@@ -546,7 +551,9 @@ public class Bundle extends DSpaceObject
             }
         }
 
-        ourContext.addEvent(new Event(Event.REMOVE, Constants.BUNDLE, getID(), Constants.BITSTREAM, b.getID(), String.valueOf(b.getSequenceID())));
+        ourContext.addEvent(new Event(Event.REMOVE, Constants.BUNDLE, getID(), 
+                Constants.BITSTREAM, b.getID(), String.valueOf(b.getSequenceID()),
+                lookupIdentifiers(ourContext)));
 
         //Ensure that the last modified from the item is triggered !
         Item owningItem = (Item) getParentObject();
@@ -606,12 +613,14 @@ public class Bundle extends DSpaceObject
 
         if (modified)
         {
-            ourContext.addEvent(new Event(Event.MODIFY, Constants.BUNDLE, getID(), null));
+            ourContext.addEvent(new Event(Event.MODIFY, Constants.BUNDLE, getID(),
+                    null, lookupIdentifiers(ourContext)));
             modified = false;
         }
         if (modifiedMetadata)
         {
-            ourContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.BUNDLE, getID(), null));
+            ourContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.BUNDLE,
+                    getID(), null, lookupIdentifiers(ourContext)));
             modifiedMetadata = false;
         }
 
@@ -628,7 +637,8 @@ public class Bundle extends DSpaceObject
         log.info(LogManager.getHeader(ourContext, "delete_bundle", "bundle_id="
                 + getID()));
 
-        ourContext.addEvent(new Event(Event.DELETE, Constants.BUNDLE, getID(), getName()));
+        ourContext.addEvent(new Event(Event.DELETE, Constants.BUNDLE, getID(), 
+                getName(), lookupIdentifiers(ourContext)));
 
         // Remove from cache
         ourContext.removeCached(this, getID());

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

@@ -279,7 +279,8 @@ public class Collection extends DSpaceObject
         myPolicy.setGroup(anonymousGroup);
         myPolicy.update();
 
-        context.addEvent(new Event(Event.CREATE, Constants.COLLECTION, c.getID(), c.handle));
+        context.addEvent(new Event(Event.CREATE, Constants.COLLECTION, 
+                c.getID(), c.handle, c.lookupIdentifiers(context)));
 
         log.info(LogManager.getHeader(context, "create_collection",
                 "collection_id=" + row.getIntColumn("collection_id"))
@@ -969,7 +970,8 @@ public class Collection extends DSpaceObject
             template = null;
         }
 
-        ourContext.addEvent(new Event(Event.MODIFY, Constants.COLLECTION, getID(), "remove_template_item"));
+        ourContext.addEvent(new Event(Event.MODIFY, Constants.COLLECTION, 
+                getID(), "remove_template_item", lookupIdentifiers(ourContext)));
     }
 
     /**
@@ -999,7 +1001,9 @@ public class Collection extends DSpaceObject
 
         DatabaseManager.insert(ourContext, row);
 
-        ourContext.addEvent(new Event(Event.ADD, Constants.COLLECTION, getID(), Constants.ITEM, item.getID(), item.getHandle()));
+        ourContext.addEvent(new Event(Event.ADD, Constants.COLLECTION, getID(), 
+                Constants.ITEM, item.getID(), item.getHandle(), 
+                lookupIdentifiers(ourContext)));
     }
 
     /**
@@ -1037,7 +1041,9 @@ public class Collection extends DSpaceObject
                 getID(), item.getID());
         DatabaseManager.setConstraintImmediate(ourContext, "coll2item_item_fk");
 
-        ourContext.addEvent(new Event(Event.REMOVE, Constants.COLLECTION, getID(), Constants.ITEM, item.getID(), item.getHandle()));
+        ourContext.addEvent(new Event(Event.REMOVE, Constants.COLLECTION, 
+                getID(), Constants.ITEM, item.getID(), item.getHandle(),
+                lookupIdentifiers(ourContext)));
     }
 
     /**
@@ -1060,12 +1066,15 @@ public class Collection extends DSpaceObject
 
         if (modified)
         {
-            ourContext.addEvent(new Event(Event.MODIFY, Constants.COLLECTION, getID(), null));
+            ourContext.addEvent(new Event(Event.MODIFY, Constants.COLLECTION, 
+                    getID(), null, lookupIdentifiers(ourContext)));
             modified = false;
         }
         if (modifiedMetadata)
         {
-            ourContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.COLLECTION, getID(), getDetails()));
+            ourContext.addEvent(new Event(Event.MODIFY_METADATA, 
+                    Constants.COLLECTION, getID(), getDetails(), 
+                    lookupIdentifiers(ourContext)));
             modifiedMetadata = false;
             clearDetails();
         }
@@ -1131,7 +1140,8 @@ public class Collection extends DSpaceObject
         log.info(LogManager.getHeader(ourContext, "delete_collection",
                 "collection_id=" + getID()));
 
-        ourContext.addEvent(new Event(Event.DELETE, Constants.COLLECTION, getID(), getHandle()));
+        ourContext.addEvent(new Event(Event.DELETE, Constants.COLLECTION, 
+                getID(), getHandle(), lookupIdentifiers(ourContext)));
 
         // Remove from cache
         ourContext.removeCached(this, getID());
@@ -1566,6 +1576,7 @@ public class Collection extends DSpaceObject
     public void updateLastModified()
     {
         //Also fire a modified event since the collection HAS been modified
-        ourContext.addEvent(new Event(Event.MODIFY, Constants.COLLECTION, getID(), null));
+        ourContext.addEvent(new Event(Event.MODIFY, Constants.COLLECTION, 
+                getID(), null, lookupIdentifiers(ourContext)));
     }
 }

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

@@ -232,12 +232,15 @@ public class Community extends DSpaceObject
         myPolicy.setGroup(anonymousGroup);
         myPolicy.update();
 
-        context.addEvent(new Event(Event.CREATE, Constants.COMMUNITY, c.getID(), c.handle));
+        context.addEvent(new Event(Event.CREATE, Constants.COMMUNITY, c.getID(), 
+                c.handle, c.lookupIdentifiers(context)));
 
         // if creating a top-level Community, simulate an ADD event at the Site.
         if (parent == null)
         {
-            context.addEvent(new Event(Event.ADD, Constants.SITE, Site.SITE_ID, Constants.COMMUNITY, c.getID(), c.handle));
+            context.addEvent(new Event(Event.ADD, Constants.SITE, Site.SITE_ID, 
+                    Constants.COMMUNITY, c.getID(), c.handle, 
+                    c.lookupIdentifiers(context)));
         }
 
         log.info(LogManager.getHeader(context, "create_community",
@@ -527,12 +530,15 @@ public class Community extends DSpaceObject
 
         if (modified)
         {
-            ourContext.addEvent(new Event(Event.MODIFY, Constants.COMMUNITY, getID(), null));
+            ourContext.addEvent(new Event(Event.MODIFY, Constants.COMMUNITY, 
+                    getID(), null, lookupIdentifiers(ourContext)));
             modified = false;
         }
         if (modifiedMetadata)
         {
-            ourContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.COMMUNITY, getID(), getDetails()));
+            ourContext.addEvent(new Event(Event.MODIFY_METADATA, 
+                    Constants.COMMUNITY, getID(), getDetails(), 
+                    lookupIdentifiers(ourContext)));
             modifiedMetadata = false;
             clearDetails();
         }
@@ -903,7 +909,9 @@ public class Community extends DSpaceObject
                 mappingRow.setColumn("community_id", getID());
                 mappingRow.setColumn("collection_id", c.getID());
 
-                ourContext.addEvent(new Event(Event.ADD, Constants.COMMUNITY, getID(), Constants.COLLECTION, c.getID(), c.getHandle()));
+                ourContext.addEvent(new Event(Event.ADD, Constants.COMMUNITY, 
+                        getID(), Constants.COLLECTION, c.getID(), c.getHandle(),
+                        lookupIdentifiers(ourContext)));
 
                 DatabaseManager.insert(ourContext, mappingRow);
             }
@@ -978,7 +986,9 @@ public class Community extends DSpaceObject
                 mappingRow.setColumn("parent_comm_id", getID());
                 mappingRow.setColumn("child_comm_id", c.getID());
 
-                ourContext.addEvent(new Event(Event.ADD, Constants.COMMUNITY, getID(), Constants.COMMUNITY, c.getID(), c.getHandle()));
+                ourContext.addEvent(new Event(Event.ADD, Constants.COMMUNITY, 
+                        getID(), Constants.COMMUNITY, c.getID(), c.getHandle(),
+                        lookupIdentifiers(ourContext)));
 
                 DatabaseManager.insert(ourContext, mappingRow);
             }
@@ -1016,6 +1026,7 @@ public class Community extends DSpaceObject
             // Capture ID & Handle of Collection we are removing, so we can trigger events later
             int removedId = c.getID();
             String removedHandle = c.getHandle();
+            String[] removedIdentifiers = c.lookupIdentifiers(ourContext);
 
             // How many parent(s) does this collection have?
             TableRow trow = DatabaseManager.querySingle(ourContext,
@@ -1041,7 +1052,8 @@ public class Community extends DSpaceObject
             log.info(LogManager.getHeader(ourContext, "remove_collection",
                     "community_id=" + getID() + ",collection_id=" + removedId));
         
-            ourContext.addEvent(new Event(Event.REMOVE, Constants.COMMUNITY, getID(), Constants.COLLECTION, removedId, removedHandle));
+            ourContext.addEvent(new Event(Event.REMOVE, Constants.COMMUNITY, getID(), 
+                    Constants.COLLECTION, removedId, removedHandle, removedIdentifiers));
         }
         catch(SQLException|IOException e)
         {
@@ -1075,6 +1087,7 @@ public class Community extends DSpaceObject
             // Capture ID & Handle of Community we are removing, so we can trigger events later
             int removedId = c.getID();
             String removedHandle = c.getHandle();
+            String[] removedIdentifiers = c.lookupIdentifiers(ourContext);
         
             // How many parent(s) does this subcommunity have?
             TableRow trow = DatabaseManager.querySingle(ourContext,
@@ -1100,7 +1113,7 @@ public class Community extends DSpaceObject
             log.info(LogManager.getHeader(ourContext, "remove_subcommunity",
                     "parent_comm_id=" + getID() + ",child_comm_id=" + removedId));
 
-            ourContext.addEvent(new Event(Event.REMOVE, Constants.COMMUNITY, getID(), Constants.COMMUNITY, removedId, removedHandle));
+            ourContext.addEvent(new Event(Event.REMOVE, Constants.COMMUNITY, getID(), Constants.COMMUNITY, removedId, removedHandle, removedIdentifiers));
         }
         catch(SQLException|IOException e)
         {
@@ -1145,7 +1158,7 @@ public class Community extends DSpaceObject
 
             // Since this is a top level Community, simulate a REMOVE event at the Site.
             ourContext.addEvent(new Event(Event.REMOVE, Constants.SITE, Site.SITE_ID,
-                    Constants.COMMUNITY, getID(), getHandle()));
+                    Constants.COMMUNITY, getID(), getHandle(), lookupIdentifiers(ourContext)));
         } else {
             // This is a subcommunity, so let the parent remove it
             // NOTE: this essentially just logs event and calls "rawDelete()"
@@ -1169,6 +1182,7 @@ public class Community extends DSpaceObject
         // Capture ID & Handle of object we are removing, so we can trigger events later
         int deletedId = getID();
         String deletedHandle = getHandle();
+        String[] deletedIdentifiers = lookupIdentifiers(ourContext);
 
         // Remove Community object from cache
         ourContext.removeCached(this, getID());
@@ -1219,7 +1233,7 @@ public class Community extends DSpaceObject
         }
 
         // If everything above worked, then trigger any associated events
-        ourContext.addEvent(new Event(Event.DELETE, Constants.COMMUNITY, deletedId, deletedHandle));
+        ourContext.addEvent(new Event(Event.DELETE, Constants.COMMUNITY, deletedId, deletedHandle, deletedIdentifiers));
     }
 
     /**
@@ -1386,6 +1400,7 @@ public class Community extends DSpaceObject
     public void updateLastModified()
     {
         //Also fire a modified event since the community HAS been modified
-        ourContext.addEvent(new Event(Event.MODIFY, Constants.COMMUNITY, getID(), null));
+        ourContext.addEvent(new Event(Event.MODIFY, Constants.COMMUNITY, 
+                getID(), null, lookupIdentifiers(ourContext)));
     }
 }

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

@@ -8,18 +8,24 @@
 package org.dspace.content;
 
 import java.sql.SQLException;
+import org.apache.log4j.Logger;
 
 import org.dspace.authorize.AuthorizeException;
 import org.dspace.core.Constants;
 import org.dspace.core.Context;
 import org.dspace.eperson.EPerson;
 import org.dspace.eperson.Group;
+import org.dspace.handle.HandleManager;
+import org.dspace.identifier.IdentifierService;
+import org.dspace.utils.DSpace;
 
 /**
  * Abstract base class for DSpace objects
  */
 public abstract class DSpaceObject
 {
+    private static final Logger log = Logger.getLogger(DSpaceObject.class);
+    
     // accumulate information to add to "detail" element of content Event,
     // e.g. to document metadata fields touched, etc.
     private StringBuffer eventDetails = null;
@@ -99,6 +105,32 @@ public abstract class DSpaceObject
      */
     public abstract String getName();
     
+    /**
+     * Tries to lookup all Identifiers of this DSpaceObject.
+     * @return An array containing all found identifiers or an array with a length of 0.
+     */
+    public String[] lookupIdentifiers(Context context)
+    {
+        String[] identifiers = new String[0];
+        IdentifierService identifierService = 
+                new DSpace().getSingletonService(IdentifierService.class);
+        
+        if (identifierService != null)
+        {
+            return identifierService.lookup(context, this);
+        }
+        
+        log.warn("No IdentifierService found, will return an array containing "
+                + "the Handle only.");
+        
+        if (getHandle() != null)
+        {
+            return new String[] { HandleManager.getCanonicalForm(getHandle()) };
+        }
+
+        return new String[0];
+    }
+
     /**
      * Generic find for when the precise type of a DSO is not known, just the
      * a pair of type number and database ID.

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

@@ -224,7 +224,7 @@ public class InstallItem
 
         // Notify interested parties of newly archived Item
         c.addEvent(new Event(Event.INSTALL, Constants.ITEM, item.getID(),
-                item.getHandle()));
+                item.getHandle(), item.lookupIdentifiers(c)));
 
         // remove in-progress submission
         is.deleteWrapper();

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

@@ -200,7 +200,8 @@ public class Item extends DSpaceObject
         i.update();
         context.restoreAuthSystemState();
 
-        context.addEvent(new Event(Event.CREATE, Constants.ITEM, i.getID(), null));
+        context.addEvent(new Event(Event.CREATE, Constants.ITEM, i.getID(), 
+                null, i.lookupIdentifiers(context)));
 
         log.info(LogManager.getHeader(context, "create_item", "item_id="
                 + row.getIntColumn("item_id")));
@@ -357,7 +358,7 @@ public class Item extends DSpaceObject
             itemRow.setColumn("last_modified", lastModified);
             DatabaseManager.updateQuery(ourContext, "UPDATE item SET last_modified = ? WHERE item_id= ? ", lastModified, getID());
             //Also fire a modified event since the item HAS been modified
-            ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), null));
+            ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), null, lookupIdentifiers(ourContext)));
         } catch (SQLException e) {
             log.error(LogManager.getHeader(ourContext, "Error while updating last modified timestamp", "Item: " + getID()));
         }
@@ -1304,7 +1305,9 @@ public class Item extends DSpaceObject
         mappingRow.setColumn("bundle_id", b.getID());
         DatabaseManager.insert(ourContext, mappingRow);
 
-        ourContext.addEvent(new Event(Event.ADD, Constants.ITEM, getID(), Constants.BUNDLE, b.getID(), b.getName()));
+        ourContext.addEvent(new Event(Event.ADD, Constants.ITEM, getID(), 
+                Constants.BUNDLE, b.getID(), b.getName(), 
+                lookupIdentifiers(ourContext)));
     }
 
     /**
@@ -1345,7 +1348,8 @@ public class Item extends DSpaceObject
                 "AND bundle_id= ? ",
                 getID(), b.getID());
 
-        ourContext.addEvent(new Event(Event.REMOVE, Constants.ITEM, getID(), Constants.BUNDLE, b.getID(), b.getName()));
+        ourContext.addEvent(new Event(Event.REMOVE, Constants.ITEM, getID(), 
+                Constants.BUNDLE, b.getID(), b.getName(), lookupIdentifiers(ourContext)));
 
         // If the bundle is orphaned, it's removed
         TableRowIterator tri = DatabaseManager.query(ourContext,
@@ -1805,12 +1809,14 @@ public class Item extends DSpaceObject
 
             if (dublinCoreChanged)
             {
-                ourContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.ITEM, getID(), getDetails()));
+                ourContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.ITEM, getID(), 
+                        getDetails(), lookupIdentifiers(ourContext)));
                 clearDetails();
                 dublinCoreChanged = false;
             }
 
-            ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), null));
+            ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), 
+                    null, lookupIdentifiers(ourContext)));
             modified = false;
         }
     }
@@ -1902,7 +1908,8 @@ public class Item extends DSpaceObject
         // Update item in DB
         update();
 
-        ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), "WITHDRAW"));
+        ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), 
+                "WITHDRAW", lookupIdentifiers(ourContext)));
 
         // remove all authorization policies, saving the custom ones
         AuthorizeManager.removeAllPoliciesByDSOAndTypeNotEqualsTo(ourContext, this, ResourcePolicy.TYPE_CUSTOM);
@@ -1959,7 +1966,8 @@ public class Item extends DSpaceObject
         // Update item in DB
         update();
 
-        ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), "REINSTATE"));
+        ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), 
+                "REINSTATE", lookupIdentifiers(ourContext)));
 
         // authorization policies
         if (colls.length > 0)
@@ -1992,7 +2000,8 @@ public class Item extends DSpaceObject
         // leaving the database in an inconsistent state
         AuthorizeManager.authorizeAction(ourContext, this, Constants.REMOVE);
 
-        ourContext.addEvent(new Event(Event.DELETE, Constants.ITEM, getID(), getHandle()));
+        ourContext.addEvent(new Event(Event.DELETE, Constants.ITEM, getID(), 
+                getHandle(), lookupIdentifiers(ourContext)));
 
         log.info(LogManager.getHeader(ourContext, "delete_item", "item_id="
                 + getID()));
@@ -2414,7 +2423,8 @@ public class Item extends DSpaceObject
             // Note that updating the owning collection above will have the same effect,
             // so we only do this here if the owning collection hasn't changed.
             
-            ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), null));
+            ourContext.addEvent(new Event(Event.MODIFY, Constants.ITEM, getID(), 
+                    null, lookupIdentifiers(ourContext)));
         }
     }
     

dspace-api/src/main/java/org/dspace/eperson/EPerson.java

@@ -546,7 +546,8 @@ public class EPerson extends DSpaceObject
         log.info(LogManager.getHeader(context, "create_eperson", "eperson_id="
                 + e.getID()));
 
-        context.addEvent(new Event(Event.CREATE, Constants.EPERSON, e.getID(), null));
+        context.addEvent(new Event(Event.CREATE, Constants.EPERSON, e.getID(), 
+                null, e.lookupIdentifiers(context)));
 
         return e;
     }
@@ -576,7 +577,8 @@ public class EPerson extends DSpaceObject
             throw new EPersonDeletionException(constraintList);
         }
 
-        myContext.addEvent(new Event(Event.DELETE, Constants.EPERSON, getID(), getEmail()));
+        myContext.addEvent(new Event(Event.DELETE, Constants.EPERSON, getID(), 
+                getEmail(), lookupIdentifiers(myContext)));
 
         // Remove from cache
         myContext.removeCached(this, getID());
@@ -1005,12 +1007,14 @@ public class EPerson extends DSpaceObject
 
         if (modified)
         {
-            myContext.addEvent(new Event(Event.MODIFY, Constants.EPERSON, getID(), null));
+            myContext.addEvent(new Event(Event.MODIFY, Constants.EPERSON, 
+                    getID(), null, lookupIdentifiers(myContext)));
             modified = false;
         }
         if (modifiedMetadata)
         {
-            myContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.EPERSON, getID(), getDetails()));
+            myContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.EPERSON, 
+                    getID(), getDetails(), lookupIdentifiers(myContext)));
             modifiedMetadata = false;
             clearDetails();
         }

dspace-api/src/main/java/org/dspace/eperson/Group.java

@@ -214,7 +214,8 @@ public class Group extends DSpaceObject
         log.info(LogManager.getHeader(context, "create_group", "group_id="
                 + g.getID()));
 
-        context.addEvent(new Event(Event.CREATE, Constants.GROUP, g.getID(), null));
+        context.addEvent(new Event(Event.CREATE, Constants.GROUP, g.getID(),
+                null, g.lookupIdentifiers(context)));
 
         return g;
     }
@@ -270,7 +271,9 @@ public class Group extends DSpaceObject
         epeople.add(e);
         epeopleChanged = true;
 
-        myContext.addEvent(new Event(Event.ADD, Constants.GROUP, getID(), Constants.EPERSON, e.getID(), e.getEmail()));
+        myContext.addEvent(new Event(Event.ADD, Constants.GROUP, getID(), 
+                Constants.EPERSON, e.getID(), e.getEmail(), 
+                lookupIdentifiers(myContext)));
     }
 
     /**
@@ -292,7 +295,9 @@ public class Group extends DSpaceObject
         groups.add(g);
         groupsChanged = true;
 
-        myContext.addEvent(new Event(Event.ADD, Constants.GROUP, getID(), Constants.GROUP, g.getID(), g.getName()));
+        myContext.addEvent(new Event(Event.ADD, Constants.GROUP, getID(), 
+                Constants.GROUP, g.getID(), g.getName(), 
+                lookupIdentifiers(myContext)));
     }
 
     /**
@@ -308,7 +313,9 @@ public class Group extends DSpaceObject
         if (epeople.remove(e))
         {
             epeopleChanged = true;
-            myContext.addEvent(new Event(Event.REMOVE, Constants.GROUP, getID(), Constants.EPERSON, e.getID(), e.getEmail()));
+            myContext.addEvent(new Event(Event.REMOVE, Constants.GROUP, getID(), 
+                    Constants.EPERSON, e.getID(), e.getEmail(), 
+                    lookupIdentifiers(myContext)));
         }
     }
 
@@ -324,7 +331,9 @@ public class Group extends DSpaceObject
         if (groups.remove(g))
         {
             groupsChanged = true;
-            myContext.addEvent(new Event(Event.REMOVE, Constants.GROUP, getID(), Constants.GROUP, g.getID(), g.getName()));
+            myContext.addEvent(new Event(Event.REMOVE, Constants.GROUP, getID(), 
+                    Constants.GROUP, g.getID(), g.getName(),
+                    lookupIdentifiers(myContext)));
         }
     }
 
@@ -997,7 +1006,8 @@ public class Group extends DSpaceObject
     {
         // FIXME: authorizations
 
-        myContext.addEvent(new Event(Event.DELETE, Constants.GROUP, getID(), getName()));
+        myContext.addEvent(new Event(Event.DELETE, Constants.GROUP, getID(), 
+                getName(), lookupIdentifiers(myContext)));
 
         // Remove from cache
         myContext.removeCached(this, getID());
@@ -1105,7 +1115,8 @@ public class Group extends DSpaceObject
 
         if (modifiedMetadata)
         {
-            myContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.GROUP, getID(), getDetails()));
+            myContext.addEvent(new Event(Event.MODIFY_METADATA, Constants.GROUP, 
+                    getID(), getDetails(), lookupIdentifiers(myContext)));
             modifiedMetadata = false;
             clearDetails();
         }

dspace-api/src/main/java/org/dspace/event/Event.java

@@ -163,6 +163,22 @@ public class Event implements Serializable
      */
     private String detail;
     
+    /**
+     * Contains all identifiers of the DSpaceObject that was changed (added, 
+     * modified, deleted, ...).
+     * 
+     * All events gets fired when a context that contains events gets commited.
+     * When the delete event is fired, a deleted DSpaceObject is already gone.
+     * This array contains all identifiers of the object, not only the handle
+     * as the detail field does. The field may be an empty array if no
+     * identifiers could be found.
+     * 
+     * FIXME: As the detail field describes it would be even better if all
+     * metadata would be available to a consumer, but the identifiers are the
+     * most important once.
+     */
+    private String[] identifiers;
+
     /** unique key to bind together events from one context's transaction */
     private String transactionID;
 
@@ -182,6 +198,9 @@ public class Event implements Serializable
     /**
      * Constructor.
      * 
+     * You should consider to use 
+     * {@link Event#Event(int, int, int, java.lang.String, java.lang.String[])}.
+     * 
      * @param eventType
      *            action type, e.g. Event.ADD.
      * @param subjectType
@@ -192,17 +211,40 @@ public class Event implements Serializable
      *            detail information that depends on context.
      */
     public Event(int eventType, int subjectType, int subjectID, String detail)
+    {
+        this(eventType, subjectType, subjectID, detail, new String[0]);
+    }
+    
+    /**
+     * Constructor.
+     * 
+     * @param eventType
+     *            action type, e.g. Event.ADD.
+     * @param subjectType
+     *            DSpace Object Type of subject e.g. Constants.ITEM.
+     * @param subjectID
+     *            database ID of subject instance.
+     * @param detail
+     *            detail information that depends on context.
+     * @param identifiers
+     *            array containing all identifiers of the dso or an empty array
+     */
+    public Event(int eventType, int subjectType, int subjectID, String detail, String[] identifiers)
     {
         this.eventType = eventType;
         this.subjectType = coreTypeToMask(subjectType);
         this.subjectID = subjectID;
         timeStamp = System.currentTimeMillis();
         this.detail = detail;
+        this.identifiers = identifiers.clone();
     }
     
     /**
      * Constructor.
      * 
+     * You should consider to use 
+     * {@link Event#Event(int, int, int, int, int, java.lang.String)} instead.
+     * 
      * @param eventType
      *            action type, e.g. Event.ADD.
      * @param subjectType
@@ -218,6 +260,31 @@ public class Event implements Serializable
      */
     public Event(int eventType, int subjectType, int subjectID, int objectType,
             int objectID, String detail)
+    {
+        this(eventType, subjectType, subjectID, objectType, objectID, detail, 
+                new String[0]);
+    }
+
+    /**
+     * Constructor.
+     * 
+     * @param eventType
+     *            action type, e.g. Event.ADD.
+     * @param subjectType
+     *            DSpace Object Type of subject e.g. Constants.ITEM.
+     * @param subjectID
+     *            database ID of subject instance.
+     * @param objectType
+     *            DSpace Object Type of object e.g. Constants.BUNDLE.
+     * @param objectID
+     *            database ID of object instance.
+     * @param detail
+     *            detail information that depends on context.
+     * @param identifiers
+     *            array containing all identifiers of the dso or an empty array
+     */
+    public Event(int eventType, int subjectType, int subjectID, int objectType,
+            int objectID, String detail, String[] identifiers)
     {
         this.eventType = eventType;
         this.subjectType = coreTypeToMask(subjectType);
@@ -226,6 +293,7 @@ public class Event implements Serializable
         this.objectID = objectID;
         timeStamp = System.currentTimeMillis();
         this.detail = detail;
+        this.identifiers = identifiers.clone();
     }
 
     /**
@@ -507,6 +575,15 @@ public class Event implements Serializable
         return detail;
     }
     
+    /**
+     * @return value of detail element of the event.
+     */
+    public String[] getIdentifiers()
+    {
+        // don't return a reference to our private array, clone it.
+        return identifiers.clone();
+    }
+
     /**
      * @return value of transactionID element of the event.
      */

dspace-api/src/main/java/org/dspace/event/TestConsumer.java

@@ -10,6 +10,7 @@ package org.dspace.event;
 import java.io.PrintStream;
 import java.text.SimpleDateFormat;
 import java.util.Date;
+import org.apache.commons.lang3.ArrayUtils;
 
 import org.apache.log4j.Logger;
 import org.dspace.core.ConfigurationManager;
@@ -66,6 +67,8 @@ public class TestConsumer implements Consumer
                 + event.getObjectTypeAsString()
                 + ", ObjectID="
                 + String.valueOf(event.getObjectID())
+                + ", Identifiers="
+                + ArrayUtils.toString(event.getIdentifiers())
                 + ", TimeStamp="
                 + applyDateFormat(new Date(event.getTimeStamp()))
                 + ", user=\""

dspace-api/src/main/java/org/dspace/identifier/IdentifierService.java

@@ -34,6 +34,17 @@ public interface IdentifierService {
      */
     String lookup(Context context, DSpaceObject dso, Class<? extends Identifier> identifier);
     
+    /**
+     * Gets the identifiers all registered IdentifierProvider returns if asked 
+     * to lookup the provided DSpaceObject.
+     *
+     * @param context
+     * @param dso the object to be identified.
+     * @return the matching identifiers, or the site identifier if the object
+     *  is a Site, or an empty array if no matching identifier is found.
+     */
+    String[] lookup(Context contex, DSpaceObject dso);
+
     /**
      *
      * This will resolve a DSpaceObject based on a provided Identifier.

dspace-api/src/main/java/org/dspace/identifier/IdentifierServiceImpl.java

@@ -15,7 +15,10 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Required;
 
 import java.sql.SQLException;
+import java.util.ArrayList;
 import java.util.List;
+import org.apache.commons.lang.StringUtils;
+import org.dspace.handle.HandleManager;
 
 /**
  * The main service class used to reserve, register and resolve identifiers
@@ -134,6 +137,66 @@ public class IdentifierServiceImpl implements IdentifierService {
         return null;
     }
     
+    @Override
+    public String[] lookup(Context context, DSpaceObject dso)
+    {
+        List<String> identifiers = new ArrayList<>();
+        for (IdentifierProvider service : providers)
+        {
+            try {
+                String result = service.lookup(context, dso);
+                if (!StringUtils.isEmpty(result))
+                {
+                    if (log.isDebugEnabled())
+                    {
+                        try {
+                            log.debug("Got an identifier from " 
+                                    + service.getClass().getCanonicalName() + ".");
+                        } catch (NullPointerException ex) {
+                            log.debug(ex.getMessage(), ex);
+                        }
+                    }
+                    
+                    identifiers.add(result);
+                }
+            }
+            catch (IdentifierException ex)
+            {
+                log.error(ex.getMessage(), ex);
+            }
+        }
+        
+        try {
+            String handle = dso.getHandle();
+            if (!StringUtils.isEmpty(handle))
+            {
+                if (!identifiers.contains(handle)
+                        && !identifiers.contains("hdl:" + handle)
+                        && !identifiers.contains(HandleManager.getCanonicalForm(handle)))
+                {
+                    // The VerionedHandleIdentifierProvider gets loaded by default
+                    // it returns handles without any scheme (neither hdl: nor http:).
+                    // If the VersionedHandleIdentifierProvider is not loaded,
+                    // we adds the handle in way it would.
+                    // Generally it would be better if identifiers would be added
+                    // here in a way they could be recognized.
+                    log.info("Adding handle '" + handle + "' to the "
+                            + "array of looked up identifiers.");
+                    identifiers.add(handle);
+                }
+            }
+        }
+        catch (Exception ex)
+        {
+            // nothing is expected here, but if an exception is thrown it
+            // should not stop everything running.
+            log.error(ex.getMessage(), ex);
+        }
+        
+        log.debug("Found identifiers: " + identifiers.toString());
+        return identifiers.toArray(new String[0]);
+    }
+
     public DSpaceObject resolve(Context context, String identifier) throws IdentifierNotFoundException, IdentifierNotResolvableException{
         for (IdentifierProvider service : providers)
         {

dspace-api/src/main/java/org/dspace/versioning/VersioningConsumer.java

@@ -53,8 +53,11 @@ public class VersioningConsumer implements Consumer {
                             previousItem.setArchived(false);
                             itemsToProcess.add(previousItem);
                             //Fire a new modify event for our previous item
-                            //Due to the need to reindex the item in the search & browse index we need to fire a new event
+                            //Due to the need to reindex the item in the search 
-                            ctx.addEvent(new Event(Event.MODIFY, previousItem.getType(), previousItem.getID(), null));
+                            //and browse index we need to fire a new event
+                            ctx.addEvent(new Event(Event.MODIFY, 
+                                    previousItem.getType(), previousItem.getID(),
+                                    null, previousItem.lookupIdentifiers(ctx)));
                         }
                     }
                 }