/*
    * Copyright (C) 2007-2012 Argeo GmbH
    *
    * 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;
  
  import javax.jcr.Node;
  import javax.jcr.RepositoryException;
  
  import org.argeo.eclipse.ui.EclipseUiException;
  import org.eclipse.jface.viewers.IElementComparer;
  
  /** Element comparer for JCR node, to be used in JFace viewers. */
  public class NodeElementComparer implements IElementComparer {
  
  	public boolean equals(Object a, Object b) {
  		try {
  			if ((a instanceof Node) && (b instanceof Node)) {
  				Node nodeA = (Node) a;
  				Node nodeB = (Node) b;
  				return nodeA.getIdentifier().equals(nodeB.getIdentifier());
  			} else {
  				return a.equals(b);
  			}
  		} catch (RepositoryException e) {
  			throw new EclipseUiException("Cannot compare nodes", e);
  		}
  	}
  
  	public int hashCode(Object element) {
  		try {
  			if (element instanceof Node)
  				return ((Node) element).getIdentifier().hashCode();
  			return element.hashCode();
  		} catch (RepositoryException e) {
  			throw new EclipseUiException("Cannot get hash code", e);
  		}
  	}
  
  }