/*******************************************************************************
* Copyright (c) 1998, 2010 Oracle. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.internal.oxm.documentpreservation;
import java.util.WeakHashMap;
import org.w3c.dom.Node;
import org.eclipse.persistence.oxm.documentpreservation.DocumentPreservationPolicy;
import org.eclipse.persistence.oxm.documentpreservation.RelativePositionOrderingPolicy;
import org.eclipse.persistence.oxm.mappings.XMLMapping;
/**
* INTERNAL:
* <p><b>Purpose:</b>Provide an implementation of DocumentPreservationPolicy that maintains bidirectional
* relationships between Java Objects and the XMLNodes they originated from.
* <p><b>Responsibilities:</b><ul>
* <li>Implement abstract methods from DocumentPreservationPolicy</li>
* <li>Maintain a map of objects to nodes</li>
* <li>Maintain the reverse map of nodes to objects</li>
*
* @author mmacivor
*
*/
public class XMLBinderPolicy extends DocumentPreservationPolicy {
private WeakHashMap nodesToObjects;
private WeakHashMap objectsToNodes;
public XMLBinderPolicy() {
nodesToObjects = new WeakHashMap();
objectsToNodes = new WeakHashMap();
setNodeOrderingPolicy(new RelativePositionOrderingPolicy());
}
public void addObjectToCache(Object obj, Node node) {
addObjectToCache(obj, node, null);
}
public void addObjectToCache(Object obj, Node node, XMLMapping selfRecordMapping) {
objectsToNodes.put(obj, node);
if(selfRecordMapping != null) {
XMLBinderCacheEntry entry = (XMLBinderCacheEntry)nodesToObjects.get(node);
if(entry != null) {
entry.addSelfMappingObject(selfRecordMapping, obj);
}
} else {
XMLBinderCacheEntry entry = new XMLBinderCacheEntry(obj);
nodesToObjects.put(node, entry);
}
}
public Node getNodeForObject(Object obj) {
return (Node)objectsToNodes.get(obj);
}
public Object getObjectForNode(Node node) {
return getObjectForNode(node, null);
}
public Object getObjectForNode(Node node, XMLMapping selfRecordMapping) {
XMLBinderCacheEntry entry = (XMLBinderCacheEntry)nodesToObjects.get(node);
if(entry != null) {
if(selfRecordMapping != null) {
return entry.getSelfMappingObject(selfRecordMapping);
} else {
return entry.getRootObject();
}
}
return null;
}
public boolean shouldPreserveDocument() {
return true;
}
}