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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.schema.bootstrap;
21  
22  
23  import java.io.Serializable;
24  import java.util.Comparator;
25  
26  import javax.naming.NamingException;
27  
28  import org.apache.directory.server.schema.registries.OidRegistry;
29  import org.apache.directory.server.schema.registries.Registries;
30  import org.apache.directory.shared.ldap.util.StringTools;
31  
32  
33  /**
34   * A comparator that sorts OIDs based on their numeric id value.  Needs a 
35   * OidRegistry to properly do it's job.  Public method to set the oid 
36   * registry will be used by the server after instantiation in deserialization.
37   *
38   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
39   * @version $Rev$
40   */
41  public class NameOrNumericIdComparator implements Comparator, Serializable
42  {
43      private static final long serialVersionUID = 1L;
44      private transient OidRegistry registry;
45  
46      
47      public NameOrNumericIdComparator( OidRegistry registry )
48      {
49          this.registry = registry;
50      }
51      
52      
53      public NameOrNumericIdComparator()
54      {
55      }
56      
57      
58      /* (non-Javadoc)
59       * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
60       */
61      public int compare( Object o1, Object o2 )
62      {
63          String s1 = getNumericIdString( o1 );
64          String s2 = getNumericIdString( o2 );
65  
66          if ( s1 == null && s2 == null )
67          {
68              return 0;
69          }
70          
71          if ( s1 == null )
72          {
73              return -1;
74          }
75          
76          if ( s2 == null )
77          {
78              return 1;
79          }
80          
81          return s1.compareTo( s2 );
82      }
83      
84      
85      public void setRegistries( Registries registries )
86      {
87          registry = registries.getOidRegistry();
88      }
89      
90      
91      String getNumericIdString( Object obj )
92      {
93          String strValue;
94  
95          if ( obj == null )
96          {
97              return null;
98          }
99          
100         if ( obj instanceof String )
101         {
102             strValue = ( String ) obj;
103         }
104         else if ( obj instanceof byte[] )
105         {
106             strValue = StringTools.utf8ToString( ( byte[] ) obj ); 
107         }
108         else
109         {
110             strValue = obj.toString();
111         }
112         
113         if ( strValue.length() == 0 )
114         {
115             return "";
116         }
117 
118         if ( registry.hasOid( strValue ) )
119         {
120             try
121             {
122                 return registry.getOid( strValue );
123             }
124             catch ( NamingException e )
125             {
126                 throw new RuntimeException( "Failed to lookup OID for " + strValue, e );
127             }
128         }
129         
130         return strValue;
131     }
132 }