View Javadoc

1   /*
2    *   Copyright 2004 The Apache Software Foundation
3    *
4    *   Licensed under the Apache License, Version 2.0 (the "License");
5    *   you may not use this file except in compliance with the License.
6    *   You may obtain a copy of the License at
7    *
8    *       http://www.apache.org/licenses/LICENSE-2.0
9    *
10   *   Unless required by applicable law or agreed to in writing, software
11   *   distributed under the License is distributed on an "AS IS" BASIS,
12   *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   *   See the License for the specific language governing permissions and
14   *   limitations under the License.
15   *
16   */
17  package org.apache.ldap.server.db;
18  
19  
20  import org.apache.ldap.server.schema.SerializableComparator;
21  
22  import java.io.Serializable;
23  
24  
25  /***
26   * A TupleComparator that compares keys only.
27   * 
28   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
29   * @version $Rev: 159259 $
30   */
31  public class KeyOnlyComparator
32      implements TupleComparator, Serializable
33  {
34      private static final long serialVersionUID = 3544956549803161397L;
35  
36      /*** TODO */
37      private SerializableComparator keyComparator = null;
38  
39  
40      /***
41       * TODO Document me! 
42       *
43       * @param comparator  TODO
44       */
45      public KeyOnlyComparator( SerializableComparator comparator )
46      {
47          keyComparator = comparator;
48      }
49  
50  
51      /***
52       * Gets the comparator used to compare keys.  May be null in which
53       * case the compareKey method will throw an UnsupportedOperationException.
54       *
55       * @return the comparator for comparing keys.
56       */
57      public SerializableComparator getKeyComparator()
58      {
59          return keyComparator;
60      }
61  
62  
63      /***
64       * Will throw an UnsupportedOperationException every time.
65       *
66       * @return TODO
67       * @throws UnsupportedOperationException every time.
68       */
69      public SerializableComparator getValueComparator()
70      {
71          throw new UnsupportedOperationException();
72      }
73  
74  
75      /***
76       * Compares key Object to determine their sorting order returning a
77       * value = to, < or > than 0.
78       *
79       * @param key1 the first key to compare
80       * @param key2 the other key to compare to the first
81       * @return 0 if both are equal, a negative value less than 0 if the first
82       * is less than the second, or a postive value if the first is greater than
83       * the second byte array.
84       */
85      public int compareKey( Object key1, Object key2 )
86      {
87          return keyComparator.compare( key1, key2 );
88      }
89  
90  
91      /***
92       * Comparse value Objects to determine their sorting order returning a
93       * value = to, < or > than 0.
94       *
95       * @param value1 the first value to compare
96       * @param value2 the other value to compare to the first
97       * @return 0 if both are equal, a negative value less than 0 if the first
98       * is less than the second, or a postive value if the first is greater than
99       * the second Object.
100      */
101     public int compareValue( Object value1, Object value2 )
102     {
103         throw new UnsupportedOperationException();
104     }
105 }