1 files changed, 357 insertions, 357 deletions
diff --git a/plugins/org.eclipse.emf.cdo.server/src/org/eclipse/emf/cdo/internal/server/XRefsQueryHandler.java b/plugins/org.eclipse.emf.cdo.server/src/org/eclipse/emf/cdo/internal/server/XRefsQueryHandler.java
index 798f666ddc..53d8fc339c 100644
--- a/plugins/org.eclipse.emf.cdo.server/src/org/eclipse/emf/cdo/internal/server/XRefsQueryHandler.java
+++ b/plugins/org.eclipse.emf.cdo.server/src/org/eclipse/emf/cdo/internal/server/XRefsQueryHandler.java
@@ -1,357 +1,357 @@
-/*
- * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the Eclipse Public License v1.0
- * which accompanies this distribution, and is available at
- * http://www.eclipse.org/legal/epl-v10.html
- *
- * Contributors:
- *    Eike Stepper - initial API and implementation
- *    Stefan Winkler - Bug 331619 - Support cross-referencing (XRef) for abstract classes and class hierarchies
- */
-package org.eclipse.emf.cdo.internal.server;
-
-import org.eclipse.emf.cdo.common.branch.CDOBranch;
-import org.eclipse.emf.cdo.common.branch.CDOBranchPoint;
-import org.eclipse.emf.cdo.common.id.CDOID;
-import org.eclipse.emf.cdo.common.id.CDOIDReference;
-import org.eclipse.emf.cdo.common.id.CDOIDUtil;
-import org.eclipse.emf.cdo.common.model.CDOClassifierRef;
-import org.eclipse.emf.cdo.common.model.CDOPackageInfo;
-import org.eclipse.emf.cdo.common.model.CDOPackageRegistry;
-import org.eclipse.emf.cdo.common.model.CDOPackageUnit;
-import org.eclipse.emf.cdo.common.model.CDOPackageUnit.State;
-import org.eclipse.emf.cdo.common.model.EMFUtil;
-import org.eclipse.emf.cdo.common.protocol.CDOProtocolConstants;
-import org.eclipse.emf.cdo.common.util.CDOQueryInfo;
-import org.eclipse.emf.cdo.server.IQueryContext;
-import org.eclipse.emf.cdo.server.IQueryHandler;
-import org.eclipse.emf.cdo.server.IRepository;
-import org.eclipse.emf.cdo.server.IStore;
-import org.eclipse.emf.cdo.server.IStoreAccessor;
-import org.eclipse.emf.cdo.server.IView;
-import org.eclipse.emf.cdo.server.StoreThreadLocal;
-import org.eclipse.emf.cdo.spi.common.model.InternalCDOPackageRegistry;
-import org.eclipse.emf.cdo.spi.server.InternalRepository;
-import org.eclipse.emf.cdo.spi.server.QueryHandlerFactory;
-
-import org.eclipse.net4j.util.factory.ProductCreationException;
-
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.EClassifier;
-import org.eclipse.emf.ecore.EPackage;
-import org.eclipse.emf.ecore.EReference;
-import org.eclipse.emf.ecore.EStructuralFeature;
-
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.StringTokenizer;
-
-/**
- * @author Eike Stepper
- */
-public class XRefsQueryHandler implements IQueryHandler
-{
-  public XRefsQueryHandler()
-  {
-  }
-
-  public void executeQuery(CDOQueryInfo info, IQueryContext context)
-  {
-    IStoreAccessor accessor = StoreThreadLocal.getAccessor();
-    QueryContext xrefsContext = new QueryContext(info, context);
-    accessor.queryXRefs(xrefsContext);
-
-    CDOBranchPoint branchPoint = context;
-    CDOBranch branch = branchPoint.getBranch();
-    while (!branch.isMainBranch() && context.getResultCount() < info.getMaxResults())
-    {
-      branchPoint = branch.getBase();
-      branch = branchPoint.getBranch();
-
-      xrefsContext.setBranchPoint(branchPoint);
-      accessor.queryXRefs(xrefsContext);
-    }
-  }
-
-  public static void collectSourceCandidates(IView view, Collection<EClass> concreteTypes,
-      Map<EClass, List<EReference>> sourceCandidates)
-  {
-    InternalRepository repository = (InternalRepository)view.getRepository();
-    CDOPackageRegistry packageRegistry = repository.getPackageRegistry(false);
-
-    for (CDOPackageInfo packageInfo : packageRegistry.getPackageInfos())
-    {
-      // System.out.println();
-      // System.out.println();
-      // System.out.println(packageInfo);
-      collectSourceCandidates(packageInfo, concreteTypes, sourceCandidates);
-      // for (Entry<EClass, List<EReference>> entry : sourceCandidates.entrySet())
-      // {
-      // System.out.println(" ---> " + entry.getKey().getName());
-      // for (EReference eReference : entry.getValue())
-      // {
-      // System.out.println("      ---> " + eReference.getName());
-      // }
-      // }
-      //
-      // System.out.println();
-      // System.out.println();
-    }
-  }
-
-  public static void collectSourceCandidates(CDOPackageInfo packageInfo, Collection<EClass> concreteTypes,
-      Map<EClass, List<EReference>> sourceCandidates)
-  {
-    State state = packageInfo.getPackageUnit().getState();
-    if (state == CDOPackageUnit.State.LOADED || state == CDOPackageUnit.State.PROXY)
-    {
-      EPackage ePackage = packageInfo.getEPackage();
-      for (EClassifier eClassifier : ePackage.getEClassifiers())
-      {
-        if (eClassifier instanceof EClass)
-        {
-          collectSourceCandidates((EClass)eClassifier, concreteTypes, sourceCandidates);
-        }
-      }
-    }
-  }
-
-  public static void collectSourceCandidates(EClass eClass, Collection<EClass> concreteTypes,
-      Map<EClass, List<EReference>> sourceCandidates)
-  {
-    if (!eClass.isAbstract() && !eClass.isInterface())
-    {
-      for (EStructuralFeature eStructuralFeature : eClass.getEAllStructuralFeatures())
-      {
-        if (eStructuralFeature instanceof EReference && EMFUtil.isPersistent(eStructuralFeature))
-        {
-          collectSourceCandidates(eClass, (EReference)eStructuralFeature, concreteTypes, sourceCandidates);
-        }
-      }
-    }
-  }
-
-  public static void collectSourceCandidates(EReference eReference, Collection<EClass> concreteTypes,
-      Map<EClass, List<EReference>> sourceCandidates, CDOPackageRegistry packageRegistry)
-  {
-    EClass rootClass = eReference.getEContainingClass();
-    collectSourceCandidates(rootClass, eReference, concreteTypes, sourceCandidates);
-
-    Collection<EClass> descendentClasses = packageRegistry.getSubTypes().get(rootClass);
-    if (descendentClasses != null)
-    {
-      for (EClass candidateClass : descendentClasses)
-      {
-        collectSourceCandidates(candidateClass, eReference, concreteTypes, sourceCandidates);
-      }
-    }
-  }
-
-  public static void collectSourceCandidates(EClass eClass, EReference eReference, Collection<EClass> concreteTypes,
-      Map<EClass, List<EReference>> sourceCandidates)
-  {
-    if (!eClass.isAbstract() && !eClass.isInterface())
-    {
-      if (!eReference.isContainer() && !eReference.isContainment())
-      {
-        if (canReference(eReference.getEReferenceType(), concreteTypes))
-        {
-          List<EReference> list = sourceCandidates.get(eClass);
-          if (list == null)
-          {
-            list = new ArrayList<EReference>();
-            sourceCandidates.put(eClass, list);
-          }
-
-          list.add(eReference);
-        }
-      }
-    }
-  }
-
-  private static boolean canReference(EClass declaredType, Collection<EClass> concreteTypes)
-  {
-    for (EClass concreteType : concreteTypes)
-    {
-      if (declaredType.isSuperTypeOf(concreteType))
-      {
-        return true;
-      }
-    }
-
-    return false;
-  }
-
-  /**
-   * @author Eike Stepper
-   * @since 3.0
-   */
-  private static final class QueryContext implements IStoreAccessor.QueryXRefsContext
-  {
-    private CDOQueryInfo info;
-
-    private IQueryContext context;
-
-    private CDOBranchPoint branchPoint;
-
-    private Map<CDOID, EClass> targetObjects;
-
-    private Map<EClass, List<EReference>> sourceCandidates;
-
-    private EReference[] sourceReferences;
-
-    public QueryContext(CDOQueryInfo info, IQueryContext context)
-    {
-      this.info = info;
-      this.context = context;
-      branchPoint = context;
-    }
-
-    public void setBranchPoint(CDOBranchPoint branchPoint)
-    {
-      this.branchPoint = branchPoint;
-    }
-
-    public CDOBranch getBranch()
-    {
-      return branchPoint.getBranch();
-    }
-
-    public long getTimeStamp()
-    {
-      return branchPoint.getTimeStamp();
-    }
-
-    public Map<CDOID, EClass> getTargetObjects()
-    {
-      if (targetObjects == null)
-      {
-        IRepository repository = context.getView().getRepository();
-        IStore store = repository.getStore();
-        CDOPackageRegistry packageRegistry = repository.getPackageRegistry();
-
-        targetObjects = new HashMap<CDOID, EClass>();
-        StringTokenizer tokenizer = new StringTokenizer(info.getQueryString(), "|");
-        while (tokenizer.hasMoreTokens())
-        {
-          String val = tokenizer.nextToken();
-          CDOID id = store.createObjectID(val);
-
-          CDOClassifierRef classifierRef;
-          if (id instanceof CDOClassifierRef.Provider)
-          {
-            classifierRef = ((CDOClassifierRef.Provider)id).getClassifierRef();
-          }
-          else
-          {
-            val = tokenizer.nextToken();
-            classifierRef = new CDOClassifierRef(val);
-          }
-
-          EClass eClass = (EClass)classifierRef.resolve(packageRegistry);
-          targetObjects.put(id, eClass);
-        }
-      }
-
-      return targetObjects;
-    }
-
-    public EReference[] getSourceReferences()
-    {
-      if (sourceReferences == null)
-      {
-        sourceReferences = parseSourceReferences();
-      }
-
-      return sourceReferences;
-    }
-
-    private EReference[] parseSourceReferences()
-    {
-      List<EReference> result = new ArrayList<EReference>();
-      CDOPackageRegistry packageRegistry = context.getView().getRepository().getPackageRegistry();
-
-      String params = (String)info.getParameters().get(CDOProtocolConstants.QUERY_LANGUAGE_XREFS_SOURCE_REFERENCES);
-      if (params == null)
-      {
-        return new EReference[0];
-      }
-
-      StringTokenizer tokenizer = new StringTokenizer(params, "|");
-      while (tokenizer.hasMoreTokens())
-      {
-        String className = tokenizer.nextToken();
-        CDOClassifierRef classifierRef = new CDOClassifierRef(className);
-        EClass eClass = (EClass)classifierRef.resolve(packageRegistry);
-
-        String featureName = tokenizer.nextToken();
-        EReference sourceReference = (EReference)eClass.getEStructuralFeature(featureName);
-        result.add(sourceReference);
-      }
-
-      return result.toArray(new EReference[result.size()]);
-    }
-
-    public Map<EClass, List<EReference>> getSourceCandidates()
-    {
-      if (sourceCandidates == null)
-      {
-        sourceCandidates = new HashMap<EClass, List<EReference>>();
-        Collection<EClass> concreteTypes = getTargetObjects().values();
-        EReference[] sourceReferences = getSourceReferences();
-
-        if (sourceReferences.length != 0)
-        {
-          InternalRepository repository = (InternalRepository)context.getView().getRepository();
-          InternalCDOPackageRegistry packageRegistry = repository.getPackageRegistry(false);
-          for (EReference eReference : sourceReferences)
-          {
-            collectSourceCandidates(eReference, concreteTypes, sourceCandidates, packageRegistry);
-          }
-        }
-        else
-        {
-          collectSourceCandidates(context.getView(), concreteTypes, sourceCandidates);
-        }
-      }
-
-      return sourceCandidates;
-    }
-
-    public int getMaxResults()
-    {
-      return info.getMaxResults();
-    }
-
-    public boolean addXRef(CDOID targetID, CDOID sourceID, EReference sourceReference, int sourceIndex)
-    {
-      if (CDOIDUtil.isNull(targetID))
-      {
-        return true;
-      }
-
-      return context.addResult(new CDOIDReference(targetID, sourceID, sourceReference, sourceIndex));
-    }
-  }
-
-  /**
-   * @author Eike Stepper
-   */
-  public static class Factory extends QueryHandlerFactory
-  {
-    public Factory()
-    {
-      super(CDOProtocolConstants.QUERY_LANGUAGE_RESOURCES);
-    }
-
-    @Override
-    public XRefsQueryHandler create(String description) throws ProductCreationException
-    {
-      return new XRefsQueryHandler();
-    }
-  }
-}
+/*
+ * Copyright (c) 2004 - 2012 Eike Stepper (Berlin, Germany) and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *    Eike Stepper - initial API and implementation
+ *    Stefan Winkler - Bug 331619 - Support cross-referencing (XRef) for abstract classes and class hierarchies
+ */
+package org.eclipse.emf.cdo.internal.server;
+
+import org.eclipse.emf.cdo.common.branch.CDOBranch;
+import org.eclipse.emf.cdo.common.branch.CDOBranchPoint;
+import org.eclipse.emf.cdo.common.id.CDOID;
+import org.eclipse.emf.cdo.common.id.CDOIDReference;
+import org.eclipse.emf.cdo.common.id.CDOIDUtil;
+import org.eclipse.emf.cdo.common.model.CDOClassifierRef;
+import org.eclipse.emf.cdo.common.model.CDOPackageInfo;
+import org.eclipse.emf.cdo.common.model.CDOPackageRegistry;
+import org.eclipse.emf.cdo.common.model.CDOPackageUnit;
+import org.eclipse.emf.cdo.common.model.CDOPackageUnit.State;
+import org.eclipse.emf.cdo.common.model.EMFUtil;
+import org.eclipse.emf.cdo.common.protocol.CDOProtocolConstants;
+import org.eclipse.emf.cdo.common.util.CDOQueryInfo;
+import org.eclipse.emf.cdo.server.IQueryContext;
+import org.eclipse.emf.cdo.server.IQueryHandler;
+import org.eclipse.emf.cdo.server.IRepository;
+import org.eclipse.emf.cdo.server.IStore;
+import org.eclipse.emf.cdo.server.IStoreAccessor;
+import org.eclipse.emf.cdo.server.IView;
+import org.eclipse.emf.cdo.server.StoreThreadLocal;
+import org.eclipse.emf.cdo.spi.common.model.InternalCDOPackageRegistry;
+import org.eclipse.emf.cdo.spi.server.InternalRepository;
+import org.eclipse.emf.cdo.spi.server.QueryHandlerFactory;
+
+import org.eclipse.net4j.util.factory.ProductCreationException;
+
+import org.eclipse.emf.ecore.EClass;
+import org.eclipse.emf.ecore.EClassifier;
+import org.eclipse.emf.ecore.EPackage;
+import org.eclipse.emf.ecore.EReference;
+import org.eclipse.emf.ecore.EStructuralFeature;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.StringTokenizer;
+
+/**
+ * @author Eike Stepper
+ */
+public class XRefsQueryHandler implements IQueryHandler
+{
+  public XRefsQueryHandler()
+  {
+  }
+
+  public void executeQuery(CDOQueryInfo info, IQueryContext context)
+  {
+    IStoreAccessor accessor = StoreThreadLocal.getAccessor();
+    QueryContext xrefsContext = new QueryContext(info, context);
+    accessor.queryXRefs(xrefsContext);
+
+    CDOBranchPoint branchPoint = context;
+    CDOBranch branch = branchPoint.getBranch();
+    while (!branch.isMainBranch() && context.getResultCount() < info.getMaxResults())
+    {
+      branchPoint = branch.getBase();
+      branch = branchPoint.getBranch();
+
+      xrefsContext.setBranchPoint(branchPoint);
+      accessor.queryXRefs(xrefsContext);
+    }
+  }
+
+  public static void collectSourceCandidates(IView view, Collection<EClass> concreteTypes,
+      Map<EClass, List<EReference>> sourceCandidates)
+  {
+    InternalRepository repository = (InternalRepository)view.getRepository();
+    CDOPackageRegistry packageRegistry = repository.getPackageRegistry(false);
+
+    for (CDOPackageInfo packageInfo : packageRegistry.getPackageInfos())
+    {
+      // System.out.println();
+      // System.out.println();
+      // System.out.println(packageInfo);
+      collectSourceCandidates(packageInfo, concreteTypes, sourceCandidates);
+      // for (Entry<EClass, List<EReference>> entry : sourceCandidates.entrySet())
+      // {
+      // System.out.println(" ---> " + entry.getKey().getName());
+      // for (EReference eReference : entry.getValue())
+      // {
+      // System.out.println("      ---> " + eReference.getName());
+      // }
+      // }
+      //
+      // System.out.println();
+      // System.out.println();
+    }
+  }
+
+  public static void collectSourceCandidates(CDOPackageInfo packageInfo, Collection<EClass> concreteTypes,
+      Map<EClass, List<EReference>> sourceCandidates)
+  {
+    State state = packageInfo.getPackageUnit().getState();
+    if (state == CDOPackageUnit.State.LOADED || state == CDOPackageUnit.State.PROXY)
+    {
+      EPackage ePackage = packageInfo.getEPackage();
+      for (EClassifier eClassifier : ePackage.getEClassifiers())
+      {
+        if (eClassifier instanceof EClass)
+        {
+          collectSourceCandidates((EClass)eClassifier, concreteTypes, sourceCandidates);
+        }
+      }
+    }
+  }
+
+  public static void collectSourceCandidates(EClass eClass, Collection<EClass> concreteTypes,
+      Map<EClass, List<EReference>> sourceCandidates)
+  {
+    if (!eClass.isAbstract() && !eClass.isInterface())
+    {
+      for (EStructuralFeature eStructuralFeature : eClass.getEAllStructuralFeatures())
+      {
+        if (eStructuralFeature instanceof EReference && EMFUtil.isPersistent(eStructuralFeature))
+        {
+          collectSourceCandidates(eClass, (EReference)eStructuralFeature, concreteTypes, sourceCandidates);
+        }
+      }
+    }
+  }
+
+  public static void collectSourceCandidates(EReference eReference, Collection<EClass> concreteTypes,
+      Map<EClass, List<EReference>> sourceCandidates, CDOPackageRegistry packageRegistry)
+  {
+    EClass rootClass = eReference.getEContainingClass();
+    collectSourceCandidates(rootClass, eReference, concreteTypes, sourceCandidates);
+
+    Collection<EClass> descendentClasses = packageRegistry.getSubTypes().get(rootClass);
+    if (descendentClasses != null)
+    {
+      for (EClass candidateClass : descendentClasses)
+      {
+        collectSourceCandidates(candidateClass, eReference, concreteTypes, sourceCandidates);
+      }
+    }
+  }
+
+  public static void collectSourceCandidates(EClass eClass, EReference eReference, Collection<EClass> concreteTypes,
+      Map<EClass, List<EReference>> sourceCandidates)
+  {
+    if (!eClass.isAbstract() && !eClass.isInterface())
+    {
+      if (!eReference.isContainer() && !eReference.isContainment())
+      {
+        if (canReference(eReference.getEReferenceType(), concreteTypes))
+        {
+          List<EReference> list = sourceCandidates.get(eClass);
+          if (list == null)
+          {
+            list = new ArrayList<EReference>();
+            sourceCandidates.put(eClass, list);
+          }
+
+          list.add(eReference);
+        }
+      }
+    }
+  }
+
+  private static boolean canReference(EClass declaredType, Collection<EClass> concreteTypes)
+  {
+    for (EClass concreteType : concreteTypes)
+    {
+      if (declaredType.isSuperTypeOf(concreteType))
+      {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  /**
+   * @author Eike Stepper
+   * @since 3.0
+   */
+  private static final class QueryContext implements IStoreAccessor.QueryXRefsContext
+  {
+    private CDOQueryInfo info;
+
+    private IQueryContext context;
+
+    private CDOBranchPoint branchPoint;
+
+    private Map<CDOID, EClass> targetObjects;
+
+    private Map<EClass, List<EReference>> sourceCandidates;
+
+    private EReference[] sourceReferences;
+
+    public QueryContext(CDOQueryInfo info, IQueryContext context)
+    {
+      this.info = info;
+      this.context = context;
+      branchPoint = context;
+    }
+
+    public void setBranchPoint(CDOBranchPoint branchPoint)
+    {
+      this.branchPoint = branchPoint;
+    }
+
+    public CDOBranch getBranch()
+    {
+      return branchPoint.getBranch();
+    }
+
+    public long getTimeStamp()
+    {
+      return branchPoint.getTimeStamp();
+    }
+
+    public Map<CDOID, EClass> getTargetObjects()
+    {
+      if (targetObjects == null)
+      {
+        IRepository repository = context.getView().getRepository();
+        IStore store = repository.getStore();
+        CDOPackageRegistry packageRegistry = repository.getPackageRegistry();
+
+        targetObjects = new HashMap<CDOID, EClass>();
+        StringTokenizer tokenizer = new StringTokenizer(info.getQueryString(), "|");
+        while (tokenizer.hasMoreTokens())
+        {
+          String val = tokenizer.nextToken();
+          CDOID id = store.createObjectID(val);
+
+          CDOClassifierRef classifierRef;
+          if (id instanceof CDOClassifierRef.Provider)
+          {
+            classifierRef = ((CDOClassifierRef.Provider)id).getClassifierRef();
+          }
+          else
+          {
+            val = tokenizer.nextToken();
+            classifierRef = new CDOClassifierRef(val);
+          }
+
+          EClass eClass = (EClass)classifierRef.resolve(packageRegistry);
+          targetObjects.put(id, eClass);
+        }
+      }
+
+      return targetObjects;
+    }
+
+    public EReference[] getSourceReferences()
+    {
+      if (sourceReferences == null)
+      {
+        sourceReferences = parseSourceReferences();
+      }
+
+      return sourceReferences;
+    }
+
+    private EReference[] parseSourceReferences()
+    {
+      List<EReference> result = new ArrayList<EReference>();
+      CDOPackageRegistry packageRegistry = context.getView().getRepository().getPackageRegistry();
+
+      String params = (String)info.getParameters().get(CDOProtocolConstants.QUERY_LANGUAGE_XREFS_SOURCE_REFERENCES);
+      if (params == null)
+      {
+        return new EReference[0];
+      }
+
+      StringTokenizer tokenizer = new StringTokenizer(params, "|");
+      while (tokenizer.hasMoreTokens())
+      {
+        String className = tokenizer.nextToken();
+        CDOClassifierRef classifierRef = new CDOClassifierRef(className);
+        EClass eClass = (EClass)classifierRef.resolve(packageRegistry);
+
+        String featureName = tokenizer.nextToken();
+        EReference sourceReference = (EReference)eClass.getEStructuralFeature(featureName);
+        result.add(sourceReference);
+      }
+
+      return result.toArray(new EReference[result.size()]);
+    }
+
+    public Map<EClass, List<EReference>> getSourceCandidates()
+    {
+      if (sourceCandidates == null)
+      {
+        sourceCandidates = new HashMap<EClass, List<EReference>>();
+        Collection<EClass> concreteTypes = getTargetObjects().values();
+        EReference[] sourceReferences = getSourceReferences();
+
+        if (sourceReferences.length != 0)
+        {
+          InternalRepository repository = (InternalRepository)context.getView().getRepository();
+          InternalCDOPackageRegistry packageRegistry = repository.getPackageRegistry(false);
+          for (EReference eReference : sourceReferences)
+          {
+            collectSourceCandidates(eReference, concreteTypes, sourceCandidates, packageRegistry);
+          }
+        }
+        else
+        {
+          collectSourceCandidates(context.getView(), concreteTypes, sourceCandidates);
+        }
+      }
+
+      return sourceCandidates;
+    }
+
+    public int getMaxResults()
+    {
+      return info.getMaxResults();
+    }
+
+    public boolean addXRef(CDOID targetID, CDOID sourceID, EReference sourceReference, int sourceIndex)
+    {
+      if (CDOIDUtil.isNull(targetID))
+      {
+        return true;
+      }
+
+      return context.addResult(new CDOIDReference(targetID, sourceID, sourceReference, sourceIndex));
+    }
+  }
+
+  /**
+   * @author Eike Stepper
+   */
+  public static class Factory extends QueryHandlerFactory
+  {
+    public Factory()
+    {
+      super(CDOProtocolConstants.QUERY_LANGUAGE_RESOURCES);
+    }
+
+    @Override
+    public XRefsQueryHandler create(String description) throws ProductCreationException
+    {
+      return new XRefsQueryHandler();
+    }
+  }
+}