aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: package com.sun.xml.internal.bind.v2.runtime;
aoqi@0: 
aoqi@0: import java.util.HashSet;
aoqi@0: import java.util.IdentityHashMap;
aoqi@0: import java.util.Map;
aoqi@0: import java.util.Set;
aoqi@0: 
aoqi@0: /**
aoqi@0:  * Bi-directional map between elements, inner peers,
aoqi@0:  * and outer peers.
aoqi@0:  *
aoqi@0:  * <p>
aoqi@0:  * TODO: this should be rewritten for efficiency.
aoqi@0:  *
aoqi@0:  * @since 2.0
aoqi@0:  *
aoqi@0:  * @author
aoqi@0:  *     Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)
aoqi@0:  */
aoqi@0: public final class AssociationMap<XmlNode> {
aoqi@0:     final static class Entry<XmlNode> {
aoqi@0:         /** XML element. */
aoqi@0:         private XmlNode element;
aoqi@0:         /** inner peer, or null. */
aoqi@0:         private Object inner;
aoqi@0:         /** outer peer, or null. */
aoqi@0:         private Object outer;
aoqi@0: 
aoqi@0:         public XmlNode element() {
aoqi@0:                 return element;
aoqi@0:         }
aoqi@0:         public Object inner() {
aoqi@0:                 return inner;
aoqi@0:         }
aoqi@0:         public Object outer() {
aoqi@0:                 return outer;
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     private final Map<XmlNode,Entry<XmlNode>> byElement = new IdentityHashMap<XmlNode,Entry<XmlNode>>();
aoqi@0:     private final Map<Object,Entry<XmlNode>> byPeer = new IdentityHashMap<Object,Entry<XmlNode>>();
aoqi@0:     private final Set<XmlNode> usedNodes = new HashSet<XmlNode>();
aoqi@0: 
aoqi@0:     /** Records the new element&lt;->inner peer association. */
aoqi@0:     public void addInner( XmlNode element, Object inner ) {
aoqi@0:         Entry<XmlNode> e = byElement.get(element);
aoqi@0:         if(e!=null) {
aoqi@0:                 if(e.inner!=null)
aoqi@0:                 byPeer.remove(e.inner);
aoqi@0:             e.inner = inner;
aoqi@0:         } else {
aoqi@0:                 e = new Entry<XmlNode>();
aoqi@0:             e.element = element;
aoqi@0:             e.inner = inner;
aoqi@0:         }
aoqi@0: 
aoqi@0:         byElement.put(element,e);
aoqi@0: 
aoqi@0:         Entry<XmlNode> old = byPeer.put(inner,e);
aoqi@0:         if(old!=null) {
aoqi@0:             if(old.outer!=null)
aoqi@0:                 byPeer.remove(old.outer);
aoqi@0:             if(old.element!=null)
aoqi@0:                 byElement.remove(old.element);
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     /** Records the new element&lt;->outer peer association. */
aoqi@0:     public void addOuter( XmlNode element, Object outer ) {
aoqi@0:         Entry<XmlNode> e = byElement.get(element);
aoqi@0:         if(e!=null) {
aoqi@0:             if(e.outer!=null)
aoqi@0:                 byPeer.remove(e.outer);
aoqi@0:             e.outer = outer;
aoqi@0:         } else {
aoqi@0:             e = new Entry<XmlNode>();
aoqi@0:             e.element = element;
aoqi@0:             e.outer = outer;
aoqi@0:         }
aoqi@0: 
aoqi@0:         byElement.put(element,e);
aoqi@0: 
aoqi@0:         Entry<XmlNode> old = byPeer.put(outer,e);
aoqi@0:         if(old!=null) {
aoqi@0:             old.outer=null;
aoqi@0: 
aoqi@0:             if(old.inner==null)
aoqi@0:                 // remove this entry
aoqi@0:                 byElement.remove(old.element);
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     public void addUsed( XmlNode n ) {
aoqi@0:         usedNodes.add(n);
aoqi@0:     }
aoqi@0: 
aoqi@0:     public Entry<XmlNode> byElement( Object e ) {
aoqi@0:         return byElement.get(e);
aoqi@0:     }
aoqi@0: 
aoqi@0:     public Entry<XmlNode> byPeer( Object o ) {
aoqi@0:         return byPeer.get(o);
aoqi@0:     }
aoqi@0: 
aoqi@0:     public Object getInnerPeer( XmlNode element ) {
aoqi@0:         Entry e = byElement(element);
aoqi@0:         if(e==null)     return null;
aoqi@0:         else            return e.inner;
aoqi@0:     }
aoqi@0: 
aoqi@0:     public Object getOuterPeer( XmlNode element ) {
aoqi@0:         Entry e = byElement(element);
aoqi@0:         if(e==null)     return null;
aoqi@0:         else            return e.outer;
aoqi@0:     }
aoqi@0: }