[DS-707] Fix multithreading issues

git-svn-id: http://scm.dspace.org/svn/repo/dspace/trunk@5481 9c30dcfa-912a-0410-8fc2-9e0234be79fd

dspace-api/src/main/java/org/dspace/app/util/MetadataExposure.java

@@ -103,7 +103,11 @@ public class MetadataExposure
             return false;
 
         // for schema.element, just check schema->elementSet
-        init();
+        if (!isInitialized())
+        {
+            init();
+        }
+
         if (qualifier == null)
         {
             Set<String> elts = hiddenElementSets.get(schema);
@@ -121,10 +125,15 @@ public class MetadataExposure
         }
     }
 
-    // load maps from configuration unless it's already done.
+    private static boolean isInitialized()
-    private static void init()
     {
-        if (hiddenElementSets == null)
+        return hiddenElementSets != null;
+    }
+
+    // load maps from configuration unless it's already done.
+    private static synchronized void init()
+    {
+        if (!isInitialized())
         {
             hiddenElementSets = new HashMap<String,Set<String>>();
             hiddenElementMaps = new HashMap<String,Map<String,Set<String>>>();

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

@@ -620,7 +620,10 @@ public class MetadataField
     public static MetadataField find(Context context, int id)
             throws SQLException
     {
-        initCache(context);
+        if (!isCacheInitialized())
+        {
+            initCache(context);
+        }
 
         // 'sanity check' first.
         Integer iid = new Integer(id);
@@ -636,41 +639,40 @@ public class MetadataField
         id2field = null;
     }
 
-    // load caches if necessary
+    private static boolean isCacheInitialized()
-    private static void initCache(Context context) throws SQLException
     {
-        if (id2field != null)
+        return id2field != null;
-            return;
+    }
-
+    
-        synchronized (MetadataField.class)
+    // load caches if necessary
+    private static synchronized void initCache(Context context) throws SQLException
+    {
+        if (!isCacheInitialized())
         {
-            if (id2field == null)
+            HashMap new_id2field = new HashMap();
+            log.info("Loading MetadataField elements into cache.");
+
+            // Grab rows from DB
+            TableRowIterator tri = DatabaseManager.queryTable(context,"MetadataFieldRegistry",
+                    "SELECT * from MetadataFieldRegistry");
+
+            try
             {
-                HashMap new_id2field = new HashMap();
+                while (tri.hasNext())
-                log.info("Loading MetadataField elements into cache.");
-
-                // Grab rows from DB
-                TableRowIterator tri = DatabaseManager.queryTable(context,"MetadataFieldRegistry",
-                        "SELECT * from MetadataFieldRegistry");
-
-                try
                 {
-                    while (tri.hasNext())
+                    TableRow row = tri.next();
-                    {
+                    int fieldID = row.getIntColumn("metadata_field_id");
-                        TableRow row = tri.next();
+                    new_id2field.put(new Integer(fieldID), new MetadataField(row));
-                        int fieldID = row.getIntColumn("metadata_field_id");
-                        new_id2field.put(new Integer(fieldID), new MetadataField(row));
-                    }
                 }
-                finally
-                {
-                    // close the TableRowIterator to free up resources
-                    if (tri != null)
-                        tri.close();
-                }
-
-                id2field = new_id2field;
             }
+            finally
+            {
+                // close the TableRowIterator to free up resources
+                if (tri != null)
+                    tri.close();
+            }
+
+            id2field = new_id2field;
         }
     }
 

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

@@ -536,7 +536,11 @@ public class MetadataSchema
     public static MetadataSchema find(Context context, int id)
             throws SQLException
     {
-        initCache(context);
+        if (!isCacheInitialized())
+        {
+            initCache(context);
+        }
+        
         Integer iid = new Integer(id);
 
         // sanity check
@@ -563,7 +567,10 @@ public class MetadataSchema
         if (shortName == null)
             return null;
 
-        initCache(context);
+        if (!isCacheInitialized())
+        {
+            initCache(context);
+        }
 
         if (!name2schema.containsKey(shortName))
             return null;
@@ -578,44 +585,43 @@ public class MetadataSchema
         name2schema = null;
     }
 
-    // load caches if necessary
+    private static boolean isCacheInitialized()
-    private static void initCache(Context context) throws SQLException
     {
-        if (id2schema != null && name2schema != null)
+        return (id2schema != null && name2schema != null);
-            return;
+    }
 
-        synchronized (MetadataSchema.class)
+    // load caches if necessary
+    private static synchronized void initCache(Context context) throws SQLException
+    {
+        if (!isCacheInitialized())
         {
-            if (id2schema == null && name2schema == null)
+            log.info("Loading schema cache for fast finds");
+            HashMap new_id2schema = new HashMap();
+            HashMap new_name2schema = new HashMap();
+
+            TableRowIterator tri = DatabaseManager.queryTable(context,"MetadataSchemaRegistry",
+                    "SELECT * from MetadataSchemaRegistry");
+
+            try
             {
-                log.info("Loading schema cache for fast finds");
+                while (tri.hasNext())
-                HashMap new_id2schema = new HashMap();
-                HashMap new_name2schema = new HashMap();
-
-                TableRowIterator tri = DatabaseManager.queryTable(context,"MetadataSchemaRegistry",
-                        "SELECT * from MetadataSchemaRegistry");
-
-                try
                 {
-                    while (tri.hasNext())
+                    TableRow row = tri.next();
-                    {
-                        TableRow row = tri.next();
 
-                        MetadataSchema s = new MetadataSchema(row);
+                    MetadataSchema s = new MetadataSchema(row);
-                        new_id2schema.put(new Integer(s.schemaID), s);
+                    new_id2schema.put(new Integer(s.schemaID), s);
-                        new_name2schema.put(s.name, s);
+                    new_name2schema.put(s.name, s);
-                    }
                 }
-                finally
-                {
-                    // close the TableRowIterator to free up resources
-                    if (tri != null)
-                        tri.close();
-                }
-
-                id2schema = new_id2schema;
-                name2schema = new_name2schema;
             }
+            finally
+            {
+                // close the TableRowIterator to free up resources
+                if (tri != null)
+                    tri.close();
+            }
+
+            id2schema = new_id2schema;
+            name2schema = new_name2schema;
         }
     }
 }

dspace-api/src/main/java/org/dspace/content/authority/DCInputAuthority.java

@@ -98,7 +98,10 @@ public class DCInputAuthority extends SelfNamedPlugin implements ChoiceAuthority
             List<String> names = new ArrayList<String>();
             Iterator pi = dci.getPairsNameIterator();
             while (pi.hasNext())
+            {
                 names.add((String)pi.next());
+            }
+
             pluginNames = names.toArray(new String[names.size()]);
             log.debug("Got plugin names = "+Arrays.deepToString(pluginNames));
         }

dspace-api/src/main/java/org/dspace/search/DSQuery.java

@@ -408,7 +408,7 @@ public class DSQuery
     /**
      * Close any IndexSearcher that is currently open.
      */
-    public static void close()
+    public static synchronized void close()
     {
         if (searcher != null)
         {

dspace-api/src/main/java/org/dspace/sort/SortOption.java

@@ -44,6 +44,7 @@ import java.util.StringTokenizer;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import org.apache.log4j.Logger;
 import org.dspace.core.ConfigurationManager;
 
 /**
@@ -54,6 +55,8 @@ import org.dspace.core.ConfigurationManager;
  */
 public class SortOption
 {
+    private static final Logger log = Logger.getLogger(SortOption.class);
+
     public static final String ASCENDING  = "ASC";
     public static final String DESCENDING = "DESC";
 
@@ -77,8 +80,27 @@ public class SortOption
 
     /** the sort options available for this index */
     private static Set<SortOption> sortOptionsSet = null;
-    private static Map<Integer, SortOption> sortOptionsMap = null;
+    static {
-	
+        try
+        {
+            Set<SortOption> newSortOptionsSet = new HashSet<SortOption>();
+            int idx = 1;
+            String option;
+
+            while ( ((option = ConfigurationManager.getProperty("webui.itemlist.sort-option." + idx))) != null)
+            {
+                SortOption so = new SortOption(idx, option);
+                newSortOptionsSet.add(so);
+                idx++;
+            }
+
+            SortOption.sortOptionsSet = newSortOptionsSet;
+        }
+        catch (SortException se)
+        {
+            log.fatal("Unable to load SortOptions", se);
+        }
+    }
 	/**
 	 * Construct a new SortOption object with the given parameters
 	 * 
@@ -297,31 +319,6 @@ public class SortOption
     	return false;
     }
 
-    /**
-     * @return	a map of the configured sort options
-     */
-    public static Map<Integer, SortOption> getSortOptionsMap() throws SortException
-    {
-        if (SortOption.sortOptionsMap != null)
-            return SortOption.sortOptionsMap;
-
-        synchronized (SortOption.class)
-        {
-            if (SortOption.sortOptionsMap == null)
-            {
-                Map<Integer, SortOption> newSortOptionsMap = new HashMap<Integer, SortOption>();
-                for (SortOption so : SortOption.getSortOptions())
-                {
-                    newSortOptionsMap.put(new Integer(so.getNumber()), so);
-                }
-
-                SortOption.sortOptionsMap = newSortOptionsMap;
-            }
-        }
-
-    	return SortOption.sortOptionsMap;
-    }
-
     /**
      * Return all the configured sort options
      * @return
@@ -329,26 +326,9 @@ public class SortOption
      */
     public static Set<SortOption> getSortOptions() throws SortException
     {
-        if (SortOption.sortOptionsSet != null)
+        if (SortOption.sortOptionsSet == null)
-            return SortOption.sortOptionsSet;
-        
-        synchronized (SortOption.class)
         {
-            if (SortOption.sortOptionsSet == null)
+            throw new SortException("Sort options not loaded");
-            {
-                Set<SortOption> newSortOptionsSet = new HashSet<SortOption>();
-                int idx = 1;
-                String option;
-
-                while ( ((option = ConfigurationManager.getProperty("webui.itemlist.sort-option." + idx))) != null)
-                {
-                    SortOption so = new SortOption(idx, option);
-                    newSortOptionsSet.add(so);
-                    idx++;
-                }
-
-                SortOption.sortOptionsSet = newSortOptionsSet;
-            }
         }
 
         return SortOption.sortOptionsSet;