1 files changed, 70 insertions, 4 deletions

diff --git a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompare.java b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompare.java
index 552f856110..e2d7d6c9a3 100644
--- a/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompare.java
+++ b/plugins/org.eclipse.emf.cdo.compare/src/org/eclipse/emf/cdo/compare/CDOCompare.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2015, 2016, 2019-2021 Eike Stepper (Loehne, Germany) and others.
+ * Copyright (c) 2013, 2015, 2016, 2019-2022 Eike Stepper (Loehne, 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
@@ -64,6 +64,7 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Supplier;
 
 /**
  * A class with many overridable factory methods that help to create EMF {@link Comparison comparisons}.
@@ -76,6 +77,8 @@ public class CDOCompare
 
   private static final boolean USE_RCP_REGISTRIES;
 
+  private static final ThreadLocal<Supplier<CDOCompare>> SUPPLIER = new ThreadLocal<>();
+
   static
   {
     if (IGNORE_RCP_REGISTRIES)
@@ -107,6 +110,14 @@ public class CDOCompare
     }
   }
 
+  /**
+   * @since 4.6
+   */
+  public boolean useRCPRegistries()
+  {
+    return USE_RCP_REGISTRIES;
+  }
+
   public Comparison compare(IComparisonScope scope)
   {
     Function<EObject, String> idFunction = createIDFunction();
@@ -146,7 +157,7 @@ public class CDOCompare
   {
     Builder builder = EMFCompare.builder();
 
-    if (USE_RCP_REGISTRIES)
+    if (useRCPRegistries())
     {
       org.eclipse.emf.compare.rcp.internal.extension.IEMFCompareBuilderConfigurator configurator = //
           org.eclipse.emf.compare.rcp.internal.extension.impl.EMFCompareBuilderConfigurator.createDefault();
@@ -202,6 +213,11 @@ public class CDOCompare
 
   protected IMatchEngine.Factory.Registry createMatchEngineFactoryRegistry(IEObjectMatcher matcher, IComparisonFactory comparisonFactory)
   {
+    if (useRCPRegistries())
+    {
+      return null;
+    }
+
     IMatchEngine.Factory.Registry registry = new MatchEngineFactoryRegistryImpl();
     registry.add(new CDOMatchEngine.Factory(matcher, comparisonFactory));
     return registry;
@@ -209,6 +225,11 @@ public class CDOCompare
 
   protected IDiffEngine createDiffEngine()
   {
+    if (useRCPRegistries())
+    {
+      return null;
+    }
+
     return new CDODiffEngine();
   }
 
@@ -232,9 +253,36 @@ public class CDOCompare
     return null;
   }
 
+  /**
+   * @since 4.7
+   */
+  public static CDOCompare create()
+  {
+    Supplier<CDOCompare> supplier = SUPPLIER.get();
+    if (supplier != null)
+    {
+      SUPPLIER.remove();
+      return supplier.get();
+    }
+
+    return new CDOCompare();
+  }
+
+  /**
+   * @since 4.7
+   */
+  public static void setCompareSupplier(Supplier<CDOCompare> supplier)
+  {
+    SUPPLIER.set(supplier);
+  }
+
+  /**
+   * @deprecated As 4.7 use {@link CDOCompareUtil#getScope(Comparison)}.
+   */
+  @Deprecated
   public static IComparisonScope getScope(Comparison comparison)
   {
-    return EMFUtil.getAdapter(comparison, IComparisonScope.class);
+    return CDOCompareUtil.getScope(comparison);
   }
 
   /**
@@ -460,7 +508,10 @@ public class CDOCompare
    */
   public static class CDOMatchEngine extends DefaultMatchEngine
   {
-    CDOMatchEngine(IEObjectMatcher matcher, IComparisonFactory comparisonFactory)
+    /**
+     * @since 4.6
+     */
+    public CDOMatchEngine(IEObjectMatcher matcher, IComparisonFactory comparisonFactory)
     {
       super(matcher, comparisonFactory);
     }
@@ -483,6 +534,21 @@ public class CDOCompare
 
       private int ranking;
 
+      /**
+       * Default factory configuration used by EMF Compare diff engine factory extension point
+       *
+       * @since 4.6
+       */
+      public Factory()
+      {
+        CDOCompare compare = CDOCompare.create();
+        CDOIDFunction idFunction = compare.createIDFunction();
+        IdentifierEObjectMatcher matcher = compare.createMatcher(idFunction);
+        IEqualityHelperFactory equalityHelperFactory = compare.createEqualityHelperFactory();
+        IComparisonFactory comparisonFactory = compare.createComparisonFactory(equalityHelperFactory);
+        matchEngine = createMatchEngine(matcher, comparisonFactory);
+      }
+
       public Factory(IEObjectMatcher matcher, IComparisonFactory comparisonFactory)
       {
         matchEngine = createMatchEngine(matcher, comparisonFactory);