[396818] Add EMF Compare merge support

https://bugs.eclipse.org/bugs/show_bug.cgi?id=396818

6 files changed, 111 insertions, 828 deletions

diff --git a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompareUtil.java b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompareUtil.java
index 05d3778225..a8b927d303 100644
--- a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompareUtil.java
+++ b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompareUtil.java
@@ -14,17 +14,14 @@ import org.eclipse.emf.cdo.CDOObject;
 import org.eclipse.emf.cdo.common.branch.CDOBranch;
 import org.eclipse.emf.cdo.common.branch.CDOBranchPoint;
 import org.eclipse.emf.cdo.common.commit.CDOChangeSetData;
-import org.eclipse.emf.cdo.common.commit.CDOCommitInfo;
 import org.eclipse.emf.cdo.common.id.CDOID;
 import org.eclipse.emf.cdo.compare.CDOComparisonScope.AllContents;
 import org.eclipse.emf.cdo.compare.CDOComparisonScope.Minimal;
 import org.eclipse.emf.cdo.eresource.CDOResource;
 import org.eclipse.emf.cdo.eresource.CDOResourceFolder;
 import org.eclipse.emf.cdo.eresource.CDOResourceNode;
-import org.eclipse.emf.cdo.session.CDOSession;
 import org.eclipse.emf.cdo.spi.common.branch.CDOBranchUtil;
 import org.eclipse.emf.cdo.transaction.CDOTransaction;
-import org.eclipse.emf.cdo.util.CDOUtil;
 import org.eclipse.emf.cdo.view.CDOView;
 
 import org.eclipse.emf.common.notify.Notifier;
@@ -58,28 +55,21 @@ import java.util.Set;
  * and returns {@link Match matches} for <b>all</b> elements of its {@link EObject#eAllContents() content tree}. This scope has the advantage that the comparison can
  * be rooted at specific objects that are different from (below of) the root resource. The disadvantage is that all the transitive children of this specific object are
  * matched, whether they differ or not. Major parts of huge repositories can be loaded to the client side easily, if no attention is paid.
- * The following methods return comparisons that are based on this scope algorithm:
+ * The following method returns comparisons that are based on this scope algorithm:
  * <ul>
- * <li>{@link #compare(EObject, CDOBranchPoint)}
- * <li>{@link #compare(EObject, CDOBranchPoint, boolean)}
+ * <li>{@link #compare(CDOObject, CDOView, CDOView[])}
  * </ul>
  * <li>{@link Minimal CDOComparisonScope.Minimal} takes a {@link CDOView view}/{@link CDOTransaction transaction}
  * and returns {@link Match matches} only for the <b>changed</b> elements of the entire content tree of its {@link CDOView#getRootResource() root resource}.
  * The advantage of this scope is that CDO-specific mechanisms are used to efficiently (remotely) determine the set of changed objects. Only those and their container
  * objects are considered as matches, making this scope scale seamlessly with the overall size of a repository.
- * The following methods return comparisons that are based on this scope algorithm:
+ * The following method returns comparisons that are based on this scope algorithm:
  * <ul>
- * <li>{@link #compare(CDOView, CDOBranchPoint)}
- * <li>{@link #compare(CDOView, CDOBranchPoint, boolean)}
+ * <li>{@link #compare(CDOView, CDOView, CDOView[])}
  * </ul>
  * </ul>
- * The {@link IComparisonScope#getRight() right side} of a comparison is specified as a {@link CDOBranchPoint} which, among others, can be another {@link CDOView}
- * (which then is not closed when the comparison is closed) or a {@link CDOCommitInfo}. The {@link IComparisonScope#getOrigin() origin side} of a comparison is
- * automatically {@link CDOBranchUtil#getAncestor(CDOBranchPoint, CDOBranchPoint) determined} by inspecting the {@link CDOBranch branch tree} and used if its different from the left or right side.
- * <p>
- * The comparions returned from these factory methods are all of the type {@link CloseableComparison} and the caller is responsible to call {@link CloseableComparison#close()}
- * on them when they're not needed anymore. The reason is that the scopes may or may not open a number of addional {@link CDOView views} on the local {@link CDOSession session}
- * that need to be closed at some point.
+ * The {@link IComparisonScope#getOrigin() origin side} of a comparison is automatically {@link CDOBranchUtil#getAncestor(CDOBranchPoint, CDOBranchPoint) determined} by
+ * inspecting the {@link CDOBranch branch tree} and used if its different from the left or right side.
  * <p>
  * The {@link IEObjectMatcher matcher} used by the comparisons is based on an {@link CDOIDFunction ID function} that considers the {@link CDOID}s of the {@link CDOObject objects}.
  * {@link CDOResource Resources} and {@link CDOResourceFolder folders} are treated as normal {@link EObject}s.
@@ -88,93 +78,30 @@ import java.util.Set;
  */
 public final class CDOCompareUtil
 {
-  /**
-   * @author Eike Stepper
-   */
-  private static final class CDOMatchEngine extends DefaultMatchEngine
-  {
-    private CDOMatchEngine(IEObjectMatcher matcher, IComparisonFactory comparisonFactory)
-    {
-      super(matcher, comparisonFactory);
-    }
-
-    /**
-     * FIXME: CDO-specific.
-     */
-    @Override
-    protected void match(Comparison comparison, IComparisonScope scope, final Notifier left, final Notifier right,
-        final Notifier origin, Monitor monitor)
-    {
-      match(comparison, scope, (EObject)left, (EObject)right, (EObject)origin, monitor);
-    }
-  }
-
   private CDOCompareUtil()
   {
   }
 
   /**
-   * Same as {@link #compare(CDOView, CDOBranchPoint, boolean) compare(leftRoot, right, true)}.
-   */
-  public static CDOComparison compare(EObject leftRoot, CDOBranchPoint right)
-  {
-    return compare(leftRoot, right, true);
-  }
-
-  /**
    * Takes an arbitrary {@link CDOObject object} (including {@link CDOResourceNode resource nodes}) and returns {@link Match matches} for <b>all</b> elements of its {@link EObject#eAllContents() content tree}. This scope has the advantage that the comparison can
    * be rooted at specific objects that are different from (below of) the root resource. The disadvantage is that all the transitive children of this specific object are
    * matched, whether they differ or not. Major parts of huge repositories can be loaded to the client side easily, if no attention is paid.
    */
-  public static CDOComparison compare(EObject leftRoot, CDOBranchPoint right, boolean tryThreeWay)
+  public static Comparison compare(CDOObject left, CDOView rightView, CDOView[] originView)
   {
-    Set<Object> objectsToDeactivateOnClose = new HashSet<Object>();
-
-    CDOObject leftObject = CDOUtil.getCDOObject(leftRoot);
-    CDOView leftView = leftObject.cdoView();
-    CDOBranchPoint left = CDOBranchUtil.copyBranchPoint(leftView);
-    CDOSession session = leftView.getSession();
-
-    CDOView rightView;
-    if (right instanceof CDOView)
+    CDOView leftView = left.cdoView();
+    if (leftView.getSession() != rightView.getSession())
     {
-      rightView = (CDOView)right;
-      if (rightView.getSession() != session)
-      {
-        throw new IllegalArgumentException("Sessions are different");
-      }
-    }
-    else
-    {
-      rightView = session.openView(right);
-      objectsToDeactivateOnClose.add(rightView);
+      throw new IllegalArgumentException("Sessions are different");
     }
 
-    Notifier rightObject = rightView.getObject(leftObject);
-
-    CDOView originView = null;
-    Notifier originObject = null;
-    if (tryThreeWay)
-    {
-      CDOBranchPoint ancestor = CDOBranchUtil.getAncestor(left, right);
-      if (!ancestor.equals(left) && !ancestor.equals(right))
-      {
-        originView = session.openView(ancestor);
-        originObject = originView.getObject(leftObject);
-        objectsToDeactivateOnClose.add(originView);
-      }
-    }
+    CDOView view = openOriginView(leftView, rightView, originView);
 
-    IComparisonScope scope = new CDOComparisonScope.AllContents(leftObject, rightObject, originObject);
-    return createComparison(scope, objectsToDeactivateOnClose);
-  }
+    CDOObject right = rightView.getObject(left);
+    CDOObject origin = view == null ? null : view.getObject(left);
 
-  /**
-   * Same as {@link #compare(EObject, CDOBranchPoint, boolean) compare(leftView, right, true)}.
-   */
-  public static CDOComparison compare(CDOView leftView, CDOBranchPoint right)
-  {
-    return compare(leftView, right, true);
+    IComparisonScope scope = new CDOComparisonScope.AllContents(left, right, origin);
+    return createComparison(scope);
   }
 
   /**
@@ -183,54 +110,58 @@ public final class CDOCompareUtil
    * The advantage of this scope is that CDO-specific mechanisms are used to efficiently (remotely) determine the set of changed objects. Only those and their container
    * objects are considered as matches, making this scope scale seamlessly with the overall size of a repository.
    */
-  public static CDOComparison compare(CDOView leftView, CDOBranchPoint right, boolean tryThreeWay)
+  public static Comparison compare(CDOView leftView, CDOView rightView, CDOView[] originView)
   {
-    Set<Object> objectsToDeactivateOnClose = new HashSet<Object>();
-    CDOSession session = leftView.getSession();
+    InternalCDOSession session = (InternalCDOSession)leftView.getSession();
+    if (rightView.getSession() != session)
+    {
+      throw new IllegalArgumentException("Sessions are different");
+    }
 
-    CDOView rightView;
-    if (right instanceof CDOView)
+    CDOView view = openOriginView(leftView, rightView, originView);
+
+    Set<CDOID> ids;
+    if (view != null)
     {
-      rightView = (CDOView)right;
-      if (rightView.getSession() != session)
-      {
-        throw new IllegalArgumentException("Sessions are different");
-      }
+      MergeData mergeData = session.getMergeData(leftView, rightView, view, false);
+      ids = mergeData.getIDs();
     }
     else
     {
-      rightView = session.openView(right);
-      objectsToDeactivateOnClose.add(rightView);
+      CDOChangeSetData changeSetData = leftView.compareRevisions(rightView);
+      ids = new HashSet<CDOID>(changeSetData.getChangeKinds().keySet());
     }
 
-    CDOView originView = null;
-    if (tryThreeWay)
+    IComparisonScope scope = new CDOComparisonScope.Minimal(leftView, rightView, view, ids);
+    return createComparison(scope);
+  }
+
+  private static CDOView openOriginView(CDOView leftView, CDOView rightView, CDOView[] originView)
+  {
+    if (originView != null)
     {
+      if (originView.length != 1)
+      {
+        throw new IllegalArgumentException("originView.length != 1");
+      }
+
+      if (originView[0] != null)
+      {
+        throw new IllegalArgumentException("originView[0] != null");
+      }
+
       CDOBranchPoint ancestor = CDOBranchUtil.getAncestor(leftView, rightView);
       if (!ancestor.equals(leftView) && !ancestor.equals(rightView))
       {
-        originView = session.openView(ancestor);
-        objectsToDeactivateOnClose.add(originView);
+        originView[0] = leftView.getSession().openView(ancestor);
+        return originView[0];
       }
     }
 
-    Set<CDOID> ids;
-    if (originView != null)
-    {
-      MergeData mergeData = ((InternalCDOSession)session).getMergeData(leftView, rightView, null, false);
-      ids = mergeData.getIDs();
-    }
-    else
-    {
-      CDOChangeSetData changeSetData = leftView.compareRevisions(right);
-      ids = new HashSet<CDOID>(changeSetData.getChangeKinds().keySet());
-    }
-
-    IComparisonScope scope = new CDOComparisonScope.Minimal(leftView, rightView, originView, ids);
-    return createComparison(scope, objectsToDeactivateOnClose);
+    return null;
   }
 
-  private static EMFCompare createComparator()
+  private static Comparison createComparison(IComparisonScope scope)
   {
     Function<EObject, String> idFunction = new CDOIDFunction();
     IEObjectMatcher matcher = new IdentifierEObjectMatcher(idFunction);
@@ -238,427 +169,27 @@ public final class CDOCompareUtil
     IComparisonFactory comparisonFactory = new DefaultComparisonFactory(new DefaultEqualityHelperFactory());
     IMatchEngine matchEngine = new CDOMatchEngine(matcher, comparisonFactory);
     EMFCompare comparator = EMFCompare.builder().setMatchEngine(matchEngine).build();
-    return comparator;
-  }
 
-  private static CDOComparison createComparison(IComparisonScope scope, Set<Object> objectsToDeactivateOnClose)
-  {
-    EMFCompare comparator = createComparator();
     Comparison comparison = comparator.compare(scope);
-    return new CDOComparison(scope, comparison, objectsToDeactivateOnClose);
+    comparison.eAdapters().add(new ComparisonScopeAdapter(scope));
+    return comparison;
   }
 
-  // /**
-  // * FIXME: To be removed when bug 390849 is resolved.
-  // *
-  // * @author Eike Stepper
-  // */
-  // private static final class _EMFCompare
-  // {
-  // private IEObjectMatcher eObjectMatcher;
-  //
-  // private Monitor progressMonitor;
-  //
-  // private final IComparisonScope scope;
-  //
-  // private _EMFCompare(IComparisonScope scope)
-  // {
-  // com.google.common.base.Preconditions.checkNotNull(scope);
-  // this.scope = scope;
-  // }
-  //
-  // public static EMFCompare newComparator(IComparisonScope scope)
-  // {
-  // return null; // Just temporary fix to make the Kepler train run again!
-  //
-  // // return new EMFCompare(scope);
-  // }
-  //
-  // private static Comparison compare(IComparisonScope scope, EMFCompareConfiguration configuration,
-  // IEObjectMatcher matcher)
-  // {
-  // final IMatchEngine matchEngine = new DefaultMatchEngine(matcher)
-  // {
-  // /**
-  // * FIXME: CDO-specific.
-  // */
-  // @Override
-  // protected void match(Notifier left, Notifier right, Notifier origin)
-  // {
-  // match((EObject)left, (EObject)right, (EObject)origin);
-  // }
-  // };
-  //
-  // Comparison comparison = matchEngine.match(scope, configuration);
-  //
-  // IPostProcessor postProcessor = getPostProcessor(scope);
-  // if (postProcessor != null)
-  // {
-  // postProcessor.postMatch(comparison);
-  // }
-  //
-  // final IDiffProcessor diffBuilder = new DiffBuilder();
-  //
-  // final IDiffEngine diffEngine = new DefaultDiffEngine(diffBuilder);
-  // diffEngine.diff(comparison);
-  //
-  // if (postProcessor != null)
-  // {
-  // postProcessor.postDiff(comparison);
-  // }
-  //
-  // final IReqEngine reqEngine = new DefaultReqEngine();
-  // reqEngine.computeRequirements(comparison);
-  //
-  // if (postProcessor != null)
-  // {
-  // postProcessor.postRequirements(comparison);
-  // }
-  //
-  // final IEquiEngine equiEngine = new DefaultEquiEngine();
-  // equiEngine.computeEquivalences(comparison);
-  //
-  // if (postProcessor != null)
-  // {
-  // postProcessor.postEquivalences(comparison);
-  // }
-  //
-  // if (comparison.isThreeWay())
-  // {
-  // final IConflictDetector conflictDetector = new DefaultConflictDetector();
-  // conflictDetector.detect(comparison);
-  //
-  // if (postProcessor != null)
-  // {
-  // postProcessor.postConflicts(comparison);
-  // }
-  // }
-  //
-  // return comparison;
-  // }
-  //
-  // private static IPostProcessor getPostProcessor(IComparisonScope scope)
-  // {
-  // IPostProcessor postProcessor = null;
-  // final Iterator<PostProcessorDescriptor> postProcessorIterator = EMFCompareExtensionRegistry
-  // .getRegisteredPostProcessors().iterator();
-  // while (postProcessorIterator.hasNext() && postProcessor == null)
-  // {
-  // final PostProcessorDescriptor descriptor = postProcessorIterator.next();
-  // if (descriptor.getNsURI() != null && descriptor.getNsURI().trim().length() != 0)
-  // {
-  // final Iterator<String> nsUris = scope.getNsURIs().iterator();
-  // while (nsUris.hasNext() && postProcessor == null)
-  // {
-  // if (nsUris.next().matches(descriptor.getNsURI()))
-  // {
-  // postProcessor = descriptor.getPostProcessor();
-  // }
-  // }
-  // }
-  //
-  // if (descriptor.getResourceURI() != null && descriptor.getResourceURI().trim().length() != 0)
-  // {
-  // final Iterator<String> resourceUris = scope.getResourceURIs().iterator();
-  // while (resourceUris.hasNext() && postProcessor == null)
-  // {
-  // if (resourceUris.next().matches(descriptor.getResourceURI()))
-  // {
-  // postProcessor = descriptor.getPostProcessor();
-  // }
-  // }
-  // }
-  // }
-  // return postProcessor;
-  // }
-  //
-  // public Comparison compare()
-  // {
-  // final Monitor monitor;
-  // if (progressMonitor != null)
-  // {
-  // monitor = progressMonitor;
-  // }
-  // else
-  // {
-  // monitor = new BasicMonitor();
-  // }
-  //
-  // EqualityHelper helper = new EqualityHelper();
-  // EMFCompareConfiguration configuration = new EMFCompareConfiguration(monitor, helper);
-  // IEObjectMatcher matcher = createMatcher(helper);
-  //
-  // return compare(scope, configuration, matcher);
-  // }
-  //
-  // public EMFCompare setEObjectMatcher(IEObjectMatcher matcher)
-  // {
-  // if (matcher != null)
-  // {
-  // eObjectMatcher = matcher;
-  // }
-  // return this;
-  // }
-  //
-  // private IEObjectMatcher createMatcher(EqualityHelper helper)
-  // {
-  // return eObjectMatcher;
-  // }
-  //
-  // /**
-  // * FIXME: Remove this when bug 390846 has been resolved.
-  // *
-  // * @author Eike Stepper
-  // */
-  // private static class DefaultMatchEngine implements IMatchEngine
-  // {
-  // private Comparison comparison;
-  //
-  // private IComparisonScope comparisonScope;
-  //
-  // private IEObjectMatcher eObjectMatcher;
-  //
-  // public DefaultMatchEngine(IEObjectMatcher matcher)
-  // {
-  // com.google.common.base.Preconditions.checkNotNull(matcher);
-  // eObjectMatcher = matcher;
-  // }
-  //
-  // public Comparison match(IComparisonScope scope, EMFCompareConfiguration configuration)
-  // {
-  // comparisonScope = scope;
-  // associate(getComparison(), configuration);
-  //
-  // final Notifier left = getScope().getLeft();
-  // final Notifier right = getScope().getRight();
-  // final Notifier origin = getScope().getOrigin();
-  //
-  // getComparison().setThreeWay(origin != null);
-  //
-  // match(left, right, origin);
-  //
-  // return getComparison();
-  // }
-  //
-  // protected void match(final Notifier left, final Notifier right, final Notifier origin)
-  // {
-  // if (left instanceof ResourceSet || right instanceof ResourceSet)
-  // {
-  // match((ResourceSet)left, (ResourceSet)right, (ResourceSet)origin);
-  // }
-  // else if (left instanceof Resource || right instanceof Resource)
-  // {
-  // match((Resource)left, (Resource)right, (Resource)origin);
-  // }
-  // else if (left instanceof EObject || right instanceof EObject)
-  // {
-  // match((EObject)left, (EObject)right, (EObject)origin);
-  // }
-  // }
-  //
-  // protected void match(ResourceSet left, ResourceSet right, ResourceSet origin)
-  // {
-  // final Iterator<? extends Resource> leftChildren = getScope().getCoveredResources(left);
-  // final Iterator<? extends Resource> rightChildren = getScope().getCoveredResources(right);
-  // final Iterator<? extends Resource> originChildren;
-  // if (origin != null)
-  // {
-  // originChildren = getScope().getCoveredResources(origin);
-  // }
-  // else
-  // {
-  // originChildren = Iterators.emptyIterator();
-  // }
-  //
-  // final IResourceMatcher resourceMatcher = getResourceMatcher();
-  // final Iterable<MatchResource> mappings = resourceMatcher.createMappings(leftChildren, rightChildren,
-  // originChildren);
-  //
-  // Iterator<? extends EObject> leftEObjects = Iterators.emptyIterator();
-  // Iterator<? extends EObject> rightEObjects = Iterators.emptyIterator();
-  // Iterator<? extends EObject> originEObjects = Iterators.emptyIterator();
-  //
-  // for (MatchResource mapping : mappings)
-  // {
-  // getComparison().getMatchedResources().add(mapping);
-  //
-  // final Resource leftRes = mapping.getLeft();
-  // final Resource rightRes = mapping.getRight();
-  // final Resource originRes = mapping.getOrigin();
-  //
-  // if (leftRes != null)
-  // {
-  // leftEObjects = Iterators.concat(leftEObjects, getScope().getCoveredEObjects(leftRes));
-  // }
-  //
-  // if (rightRes != null)
-  // {
-  // rightEObjects = Iterators.concat(rightEObjects, getScope().getCoveredEObjects(rightRes));
-  // }
-  //
-  // if (originRes != null)
-  // {
-  // originEObjects = Iterators.concat(originEObjects, getScope().getCoveredEObjects(originRes));
-  // }
-  // }
-  //
-  // final Iterable<Match> matches = getEObjectMatcher().createMatches(leftEObjects, rightEObjects, originEObjects);
-  // Iterables.addAll(getComparison().getMatches(), matches);
-  // }
-  //
-  // protected void match(Resource left, Resource right, Resource origin)
-  // {
-  // // Our "roots" are Resources. Consider them matched
-  // final MatchResource match = CompareFactory.eINSTANCE.createMatchResource();
-  //
-  // match.setLeft(left);
-  // match.setRight(right);
-  // match.setOrigin(origin);
-  //
-  // if (left != null)
-  // {
-  // URI uri = left.getURI();
-  // if (uri != null)
-  // {
-  // match.setLeftURI(uri.toString());
-  // }
-  // }
-  //
-  // if (right != null)
-  // {
-  // URI uri = right.getURI();
-  // if (uri != null)
-  // {
-  // match.setRightURI(uri.toString());
-  // }
-  // }
-  //
-  // if (origin != null)
-  // {
-  // URI uri = origin.getURI();
-  // if (uri != null)
-  // {
-  // match.setOriginURI(uri.toString());
-  // }
-  // }
-  //
-  // getComparison().getMatchedResources().add(match);
-  //
-  // // We need at least two resources to match them
-  // if (atLeastTwo(left == null, right == null, origin == null))
-  // {
-  // return;
-  // }
-  //
-  // final Iterator<? extends EObject> leftEObjects;
-  // if (left != null)
-  // {
-  // leftEObjects = getScope().getCoveredEObjects(left);
-  // }
-  // else
-  // {
-  // leftEObjects = Iterators.emptyIterator();
-  // }
-  // final Iterator<? extends EObject> rightEObjects;
-  // if (right != null)
-  // {
-  // rightEObjects = getScope().getCoveredEObjects(right);
-  // }
-  // else
-  // {
-  // rightEObjects = Iterators.emptyIterator();
-  // }
-  // final Iterator<? extends EObject> originEObjects;
-  // if (origin != null)
-  // {
-  // originEObjects = getScope().getCoveredEObjects(origin);
-  // }
-  // else
-  // {
-  // originEObjects = Iterators.emptyIterator();
-  // }
-  //
-  // final Iterable<Match> matches = getEObjectMatcher().createMatches(leftEObjects, rightEObjects, originEObjects);
-  //
-  // Iterables.addAll(getComparison().getMatches(), matches);
-  // }
-  //
-  // protected void match(EObject left, EObject right, EObject origin)
-  // {
-  // if (left == null || right == null)
-  // {
-  // throw new IllegalArgumentException();
-  // }
-  //
-  // final Iterator<? extends EObject> leftEObjects = Iterators.concat(Iterators.singletonIterator(left), getScope()
-  // .getChildren(left));
-  // final Iterator<? extends EObject> rightEObjects = Iterators.concat(Iterators.singletonIterator(right),
-  // getScope().getChildren(right));
-  // final Iterator<? extends EObject> originEObjects;
-  // if (origin != null)
-  // {
-  // originEObjects = Iterators.concat(Iterators.singletonIterator(origin), getScope().getChildren(origin));
-  // }
-  // else
-  // {
-  // originEObjects = Iterators.emptyIterator();
-  // }
-  //
-  // final Iterable<Match> matches = getEObjectMatcher().createMatches(leftEObjects, rightEObjects, originEObjects);
-  //
-  // Iterables.addAll(getComparison().getMatches(), matches);
-  // }
-  //
-  // protected IResourceMatcher getResourceMatcher()
-  // {
-  // return new StrategyResourceMatcher();
-  // }
-  //
-  // protected IEObjectMatcher getEObjectMatcher()
-  // {
-  // return eObjectMatcher;
-  // }
-  //
-  // protected Comparison getComparison()
-  // {
-  // if (comparison == null)
-  // {
-  // comparison = CompareFactory.eINSTANCE.createComparison();
-  // }
-  // return comparison;
-  // }
-  //
-  // protected IComparisonScope getScope()
-  // {
-  // return comparisonScope;
-  // }
-  //
-  // protected static boolean atLeastTwo(boolean condition1, boolean condition2, boolean condition3)
-  // {
-  // // CHECKSTYLE:OFF This expression is alone in its method, and documented.
-  // return condition1 && (condition2 || condition3) || condition2 && condition3;
-  // // CHECKSTYLE:ON
-  // }
-  //
-  // private static void associate(Comparison comparison, EMFCompareConfiguration configuration)
-  // {
-  // Iterator<Adapter> eAdapters = comparison.eAdapters().iterator();
-  // while (eAdapters.hasNext())
-  // {
-  // Adapter eAdapter = eAdapters.next();
-  // if (eAdapter.isAdapterForType(EMFCompareConfiguration.class))
-  // {
-  // eAdapters.remove();
-  // if (eAdapter instanceof Adapter.Internal)
-  // {
-  // ((Adapter.Internal)eAdapter).unsetTarget(comparison);
-  // }
-  // }
-  // }
-  //
-  // comparison.eAdapters().add(configuration);
-  // configuration.setTarget(comparison);
-  // }
-  // }
-  // }
+  /**
+   * @author Eike Stepper
+   */
+  private static final class CDOMatchEngine extends DefaultMatchEngine
+  {
+    private CDOMatchEngine(IEObjectMatcher matcher, IComparisonFactory comparisonFactory)
+    {
+      super(matcher, comparisonFactory);
+    }
+
+    @Override
+    protected void match(Comparison comparison, IComparisonScope scope, final Notifier left, final Notifier right,
+        final Notifier origin, Monitor monitor)
+    {
+      match(comparison, scope, (EObject)left, (EObject)right, (EObject)origin, monitor);
+    }
+  }
 }
diff --git a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOComparison.java b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOComparison.java
deleted file mode 100644
index d7c72c57fa..0000000000
--- a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOComparison.java
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- * 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
- */
-package org.eclipse.emf.cdo.compare;
-
-import org.eclipse.net4j.util.lifecycle.LifecycleUtil;
-
-import org.eclipse.emf.compare.Comparison;
-import org.eclipse.emf.compare.scope.IComparisonScope;
-
-import java.util.Set;
-
-/**
- * A {@link Comparison comparison} that can be closed to dispose of used resources.
- *
- * @author Eike Stepper
- */
-public class CDOComparison extends DelegatingComparison implements CloseableComparison
-{
-  private final IComparisonScope scope;
-
-  private Set<Object> objectsToDeactivateOnClose;
-
-  public CDOComparison(IComparisonScope scope, Comparison delegate, Set<Object> objectsToDeactivateOnClose)
-  {
-    super(delegate);
-    this.scope = scope;
-    this.objectsToDeactivateOnClose = objectsToDeactivateOnClose;
-  }
-
-  public final IComparisonScope getScope()
-  {
-    return scope;
-  }
-
-  public boolean isClosed()
-  {
-    return delegate == null;
-  }
-
-  public void close()
-  {
-    if (delegate != null)
-    {
-      delegate = null;
-      if (objectsToDeactivateOnClose != null)
-      {
-        for (Object object : objectsToDeactivateOnClose)
-        {
-          LifecycleUtil.deactivate(object);
-        }
-
-        objectsToDeactivateOnClose = null;
-      }
-    }
-  }
-}
\ No newline at end of file
diff --git a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOComparisonScope.java b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOComparisonScope.java
index 5e402f4bf9..585f398193 100644
--- a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOComparisonScope.java
+++ b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOComparisonScope.java
@@ -11,7 +11,6 @@
 package org.eclipse.emf.cdo.compare;
 
 import org.eclipse.emf.cdo.CDOObject;
-import org.eclipse.emf.cdo.common.branch.CDOBranchPoint;
 import org.eclipse.emf.cdo.common.id.CDOID;
 import org.eclipse.emf.cdo.common.id.CDOIDUtil;
 import org.eclipse.emf.cdo.common.revision.CDORevision;
@@ -65,10 +64,9 @@ public abstract class CDOComparisonScope extends AbstractComparisonScope
    * and returns {@link Match matches} for <b>all</b> elements of its {@link EObject#eAllContents() content tree}. This scope has the advantage that the comparison can
    * be rooted at specific objects that are different from (below of) the root resource. The disadvantage is that all the transitive children of this specific object are
    * matched, whether they differ or not. Major parts of huge repositories can be loaded to the client side easily, if no attention is paid.
-   * The following methods return comparisons that are based on this scope algorithm:
+   * The following method returns comparisons that are based on this scope algorithm:
    * <ul>
-   * <li>{@link CDOCompareUtil#compare(EObject, CDOBranchPoint)}
-   * <li>{@link CDOCompareUtil#compare(EObject, CDOBranchPoint, boolean)}
+   * <li>{@link CDOCompareUtil#compare(CDOObject, CDOView, CDOView[])}
    * </ul>
    *
    * @author Eike Stepper
@@ -91,10 +89,9 @@ public abstract class CDOComparisonScope extends AbstractComparisonScope
    * and returns {@link Match matches} only for the <b>changed</b> elements of the entire content tree of its {@link CDOView#getRootResource() root resource}.
    * The advantage of this scope is that CDO-specific mechanisms are used to efficiently (remotely) determine the set of changed objects. Only those and their container
    * objects are considered as matches, making this scope scale seamlessly with the overall size of a repository.
-   * The following methods return comparisons that are based on this scope algorithm:
+   * The following method returns comparisons that are based on this scope algorithm:
    * <ul>
-   * <li>{@link CDOCompareUtil#compare(CDOView, CDOBranchPoint)}
-   * <li>{@link CDOCompareUtil#compare(CDOView, CDOBranchPoint, boolean)}
+   * <li>{@link CDOCompareUtil#compare(CDOView, CDOView, CDOView[])}
    * </ul>
    *
    * @author Eike Stepper
diff --git a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CloseableComparison.java b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CloseableComparison.java
deleted file mode 100644
index 8830d46f81..0000000000
--- a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CloseableComparison.java
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
- * 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
- */
-package org.eclipse.emf.cdo.compare;
-
-import org.eclipse.net4j.util.collection.Closeable;
-
-import org.eclipse.emf.compare.Comparison;
-
-/**
- * A {@link Comparison comparison} that can be closed to dispose of used resources.
- * @author Eike Stepper
- */
-public interface CloseableComparison extends Comparison, Closeable
-{
-}
diff --git a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/ComparisonScopeAdapter.java b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/ComparisonScopeAdapter.java
new file mode 100644
index 0000000000..c8b1cdbf7f
--- /dev/null
+++ b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/ComparisonScopeAdapter.java
@@ -0,0 +1,38 @@
+/*
+ * 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
+ */
+package org.eclipse.emf.cdo.compare;
+
+import org.eclipse.emf.common.notify.impl.AdapterImpl;
+import org.eclipse.emf.compare.scope.IComparisonScope;
+
+/**
+ * @author Eike Stepper
+ */
+public final class ComparisonScopeAdapter extends AdapterImpl
+{
+  private IComparisonScope scope;
+
+  public ComparisonScopeAdapter(IComparisonScope scope)
+  {
+    this.scope = scope;
+  }
+
+  public final IComparisonScope getScope()
+  {
+    return scope;
+  }
+
+  @Override
+  public boolean isAdapterForType(Object type)
+  {
+    return type == ComparisonScopeAdapter.class;
+  }
+}
diff --git a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/DelegatingComparison.java b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/DelegatingComparison.java
deleted file mode 100644
index 47e8112bd9..0000000000
--- a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/DelegatingComparison.java
+++ /dev/null
@@ -1,196 +0,0 @@
-/*
- * 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
- */
-package org.eclipse.emf.cdo.compare;
-
-import org.eclipse.emf.common.notify.Adapter;
-import org.eclipse.emf.common.notify.Notification;
-import org.eclipse.emf.common.util.EList;
-import org.eclipse.emf.common.util.TreeIterator;
-import org.eclipse.emf.compare.Comparison;
-import org.eclipse.emf.compare.Conflict;
-import org.eclipse.emf.compare.Diff;
-import org.eclipse.emf.compare.Equivalence;
-import org.eclipse.emf.compare.Match;
-import org.eclipse.emf.compare.MatchResource;
-import org.eclipse.emf.compare.utils.IEqualityHelper;
-import org.eclipse.emf.ecore.EClass;
-import org.eclipse.emf.ecore.EObject;
-import org.eclipse.emf.ecore.EOperation;
-import org.eclipse.emf.ecore.EReference;
-import org.eclipse.emf.ecore.EStructuralFeature;
-import org.eclipse.emf.ecore.resource.Resource;
-
-import java.lang.reflect.InvocationTargetException;
-
-/**
- * A {@link Comparison comparison} that delegates all methods to another comparison.
- *
- * @author Eike Stepper
- */
-public class DelegatingComparison implements Comparison
-{
-  protected Comparison delegate;
-
-  public DelegatingComparison(Comparison delegate)
-  {
-    this.delegate = delegate;
-  }
-
-  public Comparison getDelegate()
-  {
-    return delegate;
-  }
-
-  public EList<Adapter> eAdapters()
-  {
-    return delegate.eAdapters();
-  }
-
-  public boolean eDeliver()
-  {
-    return delegate.eDeliver();
-  }
-
-  public void eSetDeliver(boolean deliver)
-  {
-    delegate.eSetDeliver(deliver);
-  }
-
-  public void eNotify(Notification notification)
-  {
-    delegate.eNotify(notification);
-  }
-
-  public EList<MatchResource> getMatchedResources()
-  {
-    return delegate.getMatchedResources();
-  }
-
-  public EList<Match> getMatches()
-  {
-    return delegate.getMatches();
-  }
-
-  public EClass eClass()
-  {
-    return delegate.eClass();
-  }
-
-  public EList<Conflict> getConflicts()
-  {
-    return delegate.getConflicts();
-  }
-
-  public Resource eResource()
-  {
-    return delegate.eResource();
-  }
-
-  public EList<Equivalence> getEquivalences()
-  {
-    return delegate.getEquivalences();
-  }
-
-  public EObject eContainer()
-  {
-    return delegate.eContainer();
-  }
-
-  public IEqualityHelper getEqualityHelper()
-  {
-    return delegate.getEqualityHelper();
-  }
-
-  public EList<Diff> getDifferences()
-  {
-    return delegate.getDifferences();
-  }
-
-  public EStructuralFeature eContainingFeature()
-  {
-    return delegate.eContainingFeature();
-  }
-
-  public EList<Diff> getDifferences(EObject element)
-  {
-    return delegate.getDifferences(element);
-  }
-
-  public Match getMatch(EObject element)
-  {
-    return delegate.getMatch(element);
-  }
-
-  public EReference eContainmentFeature()
-  {
-    return delegate.eContainmentFeature();
-  }
-
-  public boolean isThreeWay()
-  {
-    return delegate.isThreeWay();
-  }
-
-  public void setThreeWay(boolean value)
-  {
-    delegate.setThreeWay(value);
-  }
-
-  public EList<EObject> eContents()
-  {
-    return delegate.eContents();
-  }
-
-  public TreeIterator<EObject> eAllContents()
-  {
-    return delegate.eAllContents();
-  }
-
-  public boolean eIsProxy()
-  {
-    return delegate.eIsProxy();
-  }
-
-  public EList<EObject> eCrossReferences()
-  {
-    return delegate.eCrossReferences();
-  }
-
-  public Object eGet(EStructuralFeature feature)
-  {
-    return delegate.eGet(feature);
-  }
-
-  public Object eGet(EStructuralFeature feature, boolean resolve)
-  {
-    return delegate.eGet(feature, resolve);
-  }
-
-  public void eSet(EStructuralFeature feature, Object newValue)
-  {
-    delegate.eSet(feature, newValue);
-  }
-
-  public boolean eIsSet(EStructuralFeature feature)
-  {
-    return delegate.eIsSet(feature);
-  }
-
-  public void eUnset(EStructuralFeature feature)
-  {
-    delegate.eUnset(feature);
-  }
-
-  public Object eInvoke(EOperation operation, EList<?> arguments) throws InvocationTargetException
-  {
-    return delegate.eInvoke(operation, arguments);
-  }
-}