[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
+        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 void init()
+    private static boolean isInitialized()
     {
-        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

@@ -619,8 +619,11 @@ public class MetadataField
      */
     public static MetadataField find(Context context, int id)
             throws SQLException
+    {
+        if (!isCacheInitialized())
         {
             initCache(context);
+        }
 
         // 'sanity check' first.
         Integer iid = new Integer(id);
@@ -636,15 +639,15 @@ public class MetadataField
         id2field = null;
     }
 
-    // load caches if necessary
-    private static void initCache(Context context) throws SQLException
+    private static boolean isCacheInitialized()
     {
-        if (id2field != null)
-            return;
+        return id2field != null;
+    }
     
-        synchronized (MetadataField.class)
+    // load caches if necessary
+    private static synchronized void initCache(Context context) throws SQLException
     {
-            if (id2field == null)
+        if (!isCacheInitialized())
         {
             HashMap new_id2field = new HashMap();
             log.info("Loading MetadataField elements into cache.");
@@ -672,7 +675,6 @@ public class MetadataField
             id2field = new_id2field;
         }
     }
-    }
 
     /**
      * Return <code>true</code> if <code>other</code> is the same MetadataField

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

@@ -535,8 +535,12 @@ public class MetadataSchema
      */
     public static MetadataSchema find(Context context, int id)
             throws SQLException
+    {
+        if (!isCacheInitialized())
         {
             initCache(context);
+        }
+        
         Integer iid = new Integer(id);
 
         // sanity check
@@ -563,7 +567,10 @@ public class MetadataSchema
         if (shortName == null)
             return null;
 
+        if (!isCacheInitialized())
+        {
             initCache(context);
+        }
 
         if (!name2schema.containsKey(shortName))
             return null;
@@ -578,15 +585,15 @@ public class MetadataSchema
         name2schema = null;
     }
 
-    // load caches if necessary
-    private static void initCache(Context context) throws SQLException
+    private static boolean isCacheInitialized()
     {
-        if (id2schema != null && name2schema != null)
-            return;
+        return (id2schema != null && name2schema != null);
+    }
 
-        synchronized (MetadataSchema.class)
+    // load caches if necessary
+    private static synchronized void initCache(Context context) throws SQLException
     {
-            if (id2schema == null && name2schema == null)
+        if (!isCacheInitialized())
         {
             log.info("Loading schema cache for fast finds");
             HashMap new_id2schema = new HashMap();
@@ -617,5 +624,4 @@ public class MetadataSchema
             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
 	 * 
@@ -297,58 +319,16 @@ 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
      * @throws SortException
      */
     public static Set<SortOption> getSortOptions() throws SortException
-    {
-        if (SortOption.sortOptionsSet != null)
-            return SortOption.sortOptionsSet;
-        
-        synchronized (SortOption.class)
     {
         if (SortOption.sortOptionsSet == null)
         {
-                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;
-            }
+            throw new SortException("Sort options not loaded");
         }
 
         return SortOption.sortOptionsSet;