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1   /*
2    *  Licensed to the Apache Software Foundation (ASF) under one
3    *  or more contributor license agreements.  See the NOTICE file
4    *  distributed with this work for additional information
5    *  regarding copyright ownership.  The ASF licenses this file
6    *  to you under the Apache License, Version 2.0 (the
7    *  "License"); you may not use this file except in compliance
8    *  with the License.  You may obtain a copy of the License at
9    *  
10   *    http://www.apache.org/licenses/LICENSE-2.0
11   *  
12   *  Unless required by applicable law or agreed to in writing,
13   *  software distributed under the License is distributed on an
14   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   *  KIND, either express or implied.  See the License for the
16   *  specific language governing permissions and limitations
17   *  under the License. 
18   *  
19   */
20  package org.apache.directory.server.xdbm;
21  
22  
23  /**
24   * An index id value pair based on a Tuple which can optionally reference the
25   * indexed obj if one has already been loaded.
26   * 
27   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
28   * @version $Rev: 642800 $
29   */
30  public class ForwardIndexEntry<V,O> implements IndexEntry<V,O>
31  {
32      /** The underlying Tuple */
33      private final Tuple<V,Long> tuple = new Tuple<V,Long>();
34  
35      /** The referenced obj if loaded from the store */
36      private O obj;
37  
38  
39      /**
40       * Sets the key value tuple represented by this ForwardIndexEntry optionally
41       * setting the obj associated with the id if one was loaded from the
42       * master table.
43       *
44       * @param tuple the tuple for the ForwardIndexEntry
45       * @param entry the resusitated obj if any
46       */
47      public void setTuple( Tuple<V,Long> tuple, O entry )
48      {
49          this.tuple.setKey( tuple.getKey() );
50          this.tuple.setValue( tuple.getValue() );
51          this.obj = entry;
52      }
53  
54  
55      public Long getId()
56      {
57          return tuple.getValue();
58      }
59  
60  
61      public V getValue()
62      {
63          return tuple.getKey();
64      }
65  
66  
67      public void setId( Long id )
68      {
69          tuple.setValue( id );
70      }
71  
72  
73      public void setValue( V value )
74      {
75          tuple.setKey( value );
76      }
77  
78  
79      public O getObject()
80      {
81          if ( obj == null )
82          {
83              return null;
84          }
85  
86          return obj;
87      }
88  
89  
90      public void setObject( O obj )
91      {
92          this.obj = obj;
93      }
94  
95  
96      public Tuple getTuple()
97      {
98          return tuple;
99      }
100 
101 
102     public void clear()
103     {
104         obj = null;
105         tuple.setKey( null );
106         tuple.setValue( null );
107     }
108 
109 
110     public void copy( IndexEntry<V, O> entry )
111     {
112         this.obj = entry.getObject();
113         tuple.setKey( entry.getValue() );
114         tuple.setValue( entry.getId() );
115     }
116 
117 
118     public String toString()
119     {
120         StringBuilder buf = new StringBuilder();
121         buf.append( "ForwardIndexEntry[ " );
122         buf.append( tuple.getKey() );
123         buf.append( ", " );
124         buf.append( tuple.getValue() );
125         buf.append( " ]" );
126         return buf.toString();
127     }
128 }