1 /*
   2  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.xml.internal.bind.v2.runtime;
  27 
  28 import java.util.HashSet;
  29 import java.util.IdentityHashMap;
  30 import java.util.Map;
  31 import java.util.Set;
  32 
  33 /**
  34  * Bi-directional map between elements, inner peers,
  35  * and outer peers.
  36  *
  37  * <p>
  38  * TODO: this should be rewritten for efficiency.
  39  *
  40  * @since 2.0
  41  *
  42  * @author
  43  *     Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)
  44  */
  45 public final class AssociationMap<XmlNode> {
  46     final static class Entry<XmlNode> {
  47         /** XML element. */
  48         private XmlNode element;
  49         /** inner peer, or null. */
  50         private Object inner;
  51         /** outer peer, or null. */
  52         private Object outer;
  53 
  54         public XmlNode element() {
  55                 return element;
  56         }
  57         public Object inner() {
  58                 return inner;
  59         }
  60         public Object outer() {
  61                 return outer;
  62         }
  63     }
  64 
  65     private final Map<XmlNode,Entry<XmlNode>> byElement = new IdentityHashMap<XmlNode,Entry<XmlNode>>();
  66     private final Map<Object,Entry<XmlNode>> byPeer = new IdentityHashMap<Object,Entry<XmlNode>>();
  67     private final Set<XmlNode> usedNodes = new HashSet<XmlNode>();
  68 
  69     /** Records the new {@code element <->inner} peer association. */
  70     public void addInner( XmlNode element, Object inner ) {
  71         Entry<XmlNode> e = byElement.get(element);
  72         if(e!=null) {
  73                 if(e.inner!=null)
  74                 byPeer.remove(e.inner);
  75             e.inner = inner;
  76         } else {
  77                 e = new Entry<XmlNode>();
  78             e.element = element;
  79             e.inner = inner;
  80         }
  81 
  82         byElement.put(element,e);
  83 
  84         Entry<XmlNode> old = byPeer.put(inner,e);
  85         if(old!=null) {
  86             if(old.outer!=null)
  87                 byPeer.remove(old.outer);
  88             if(old.element!=null)
  89                 byElement.remove(old.element);
  90         }
  91     }
  92 
  93     /** Records the new {@code element <-> outer} peer association. */
  94     public void addOuter( XmlNode element, Object outer ) {
  95         Entry<XmlNode> e = byElement.get(element);
  96         if(e!=null) {
  97             if(e.outer!=null)
  98                 byPeer.remove(e.outer);
  99             e.outer = outer;
 100         } else {
 101             e = new Entry<XmlNode>();
 102             e.element = element;
 103             e.outer = outer;
 104         }
 105 
 106         byElement.put(element,e);
 107 
 108         Entry<XmlNode> old = byPeer.put(outer,e);
 109         if(old!=null) {
 110             old.outer=null;
 111 
 112             if(old.inner==null)
 113                 // remove this entry
 114                 byElement.remove(old.element);
 115         }
 116     }
 117 
 118     public void addUsed( XmlNode n ) {
 119         usedNodes.add(n);
 120     }
 121 
 122     public Entry<XmlNode> byElement( Object e ) {
 123         return byElement.get(e);
 124     }
 125 
 126     public Entry<XmlNode> byPeer( Object o ) {
 127         return byPeer.get(o);
 128     }
 129 
 130     public Object getInnerPeer( XmlNode element ) {
 131         Entry e = byElement(element);
 132         if(e==null)     return null;
 133         else            return e.inner;
 134     }
 135 
 136     public Object getOuterPeer( XmlNode element ) {
 137         Entry e = byElement(element);
 138         if(e==null)     return null;
 139         else            return e.outer;
 140     }
 141 }
--- EOF ---