Move to Commons Base

[lgpl/argeo-commons.git] / base / runtime / org.argeo.eclipse.ui.jcr / src / main / java / org / argeo / eclipse / ui / jcr / utils / NodeViewerComparer.java

diff --git a/base/runtime/org.argeo.eclipse.ui.jcr/src/main/java/org/argeo/eclipse/ui/jcr/utils/NodeViewerComparer.java b/base/runtime/org.argeo.eclipse.ui.jcr/src/main/java/org/argeo/eclipse/ui/jcr/utils/NodeViewerComparer.java
new file mode 100644 (file)
index 0000000..4e627b0
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+++ b/base/runtime/org.argeo.eclipse.ui.jcr/src/main/java/org/argeo/eclipse/ui/jcr/utils/NodeViewerComparer.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2007-2012 Mathieu Baudier
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.argeo.eclipse.ui.jcr.utils;
+
+import javax.jcr.Node;
+import javax.jcr.RepositoryException;
+
+import org.argeo.ArgeoException;
+import org.eclipse.jface.viewers.IElementComparer;
+
+/** Compare JCR nodes based on their JCR identifiers, for use in JFace viewers. */
+public class NodeViewerComparer implements IElementComparer {
+
+       // force comparison on Node IDs only.
+       public boolean equals(Object elementA, Object elementB) {
+               if (!(elementA instanceof Node) || !(elementB instanceof Node)) {
+                       return elementA == null ? elementB == null : elementA
+                                       .equals(elementB);
+               } else {
+
+                       boolean result = false;
+                       try {
+                               String idA = ((Node) elementA).getIdentifier();
+                               String idB = ((Node) elementB).getIdentifier();
+                               result = idA == null ? idB == null : idA.equals(idB);
+                       } catch (RepositoryException re) {
+                               throw new ArgeoException("cannot compare nodes", re);
+                       }
+
+                       return result;
+               }
+       }
+
+       public int hashCode(Object element) {
+               // TODO enhanced this method.
+               return element.getClass().toString().hashCode();
+       }
+}
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