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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   * A key/value tuple for simple two column persistent Tables with sorted keys.
25   * 
26   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
27   * @version $Rev: 640657 $
28   */
29  public class Tuple<K, V>
30  {
31      /** the key for this Tuple */
32      private K key;
33      /** the value for this Tuple */
34      private V value;
35  
36  
37      /**
38       * Do nothing default that has a null key and null value.
39       */
40      public Tuple()
41      {
42          // does nothing!
43      }
44  
45  
46      /**
47       * Creates a Tuple using a key and a value.
48       * 
49       * @param key the key to set
50       * @param value the value to set
51       */
52      public Tuple( K key, V value )
53      {
54          this.key = key;
55          this.value = value;
56      }
57  
58  
59      /**
60       * Gets the key for this Tuple.
61       *
62       * @return the Tuple's key
63       */
64      public K getKey()
65      {
66          return key;
67      }
68  
69  
70      /**
71       * Sets the key for this Tuple.
72       *
73       * @param key the new key to set
74       * @return this Tuple itself to set and return
75       */
76      public Tuple<K,V> setKey( K key )
77      {
78          this.key = key;
79          return this;
80      }
81  
82  
83      /**
84       * Gets the value for this Tuple.
85       *
86       * @return the Tuple's value
87       */
88      public V getValue()
89      {
90          return value;
91      }
92  
93  
94      /**
95       * Sets the value for this Tuple.
96       *
97       * @param value the new value to set
98       * @return this Tuple itself to set and return
99       */
100     public Tuple<K,V> setValue( V value )
101     {
102         this.value = value;
103         return this;
104     }
105 
106 
107     /**
108      * Sets both the key and the value for this Tuple in one call and returns
109      * this Tuple object.  This is useful for setting the tuples key and value
110      * then returning it.
111      *
112      * @param key the new key to set
113      * @param value the new value to set
114      * @return this Tuple itself to set and return
115      */
116     public Tuple<K,V> setBoth( K key, V value )
117     {
118         this.key = key;
119         this.value = value;
120         return this;
121     }
122 
123 
124 
125 
126     /**
127      * Sets both the key and the value for this Tuple in one call and returns
128      * this Tuple object.  This is useful for setting the tuples key and value
129      * then returning it.
130      *
131      * @param tupleToCopy the tuple to copy
132      * @return this Tuple itself to set and return
133      */
134     public Tuple<K,V> setBoth( Tuple<K,V> tupleToCopy )
135     {
136         this.key = tupleToCopy.key;
137         this.value = tupleToCopy.value;
138         return this;
139     }
140 
141 
142     public String toString()
143     {
144         StringBuilder buf = new StringBuilder();
145         buf.append( "Tuple( '" );
146         buf.append( key );
147         buf.append(  "', '" );
148         buf.append( value );
149         buf.append( "' )" );
150         return buf.toString();
151     }
152 }