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1   /*
2    *   Copyright 2005 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  
18  package org.apache.asn1.der;
19  
20  
21  /***
22   * DER Enumerated object.
23   */
24  public class DEREnumerated extends DERObject
25  {
26      /***
27       * Basic DERObject constructor.
28       */
29      public DEREnumerated( byte[] value )
30      {
31      	super( ENUMERATED, value );
32      }
33      
34      /***
35       * Static factory method, type-conversion operator.
36       */
37      public static DEREnumerated valueOf( int integer )
38      {
39          return new DEREnumerated( intToOctet( integer ) );
40      }
41      
42      /***
43       * Lazy accessor
44       * @return integer value
45       */
46      public int intValue()
47      {
48          return octetToInt( value );
49      }
50      
51      private static int octetToInt( byte[] bytes )
52      {
53      	int result = 0;
54      	
55      	for ( int ii = 0; ii < Math.min( 4, bytes.length ); ii++ )
56      	{
57      		result += bytes[ ii ] * ( 16 ^ ii );
58      	}
59      	return result;
60      }
61  	
62      private static byte[] intToOctet( int integer )
63      {
64          byte[] result = new byte[ 4 ];
65          
66          for ( int ii = 0, shift = 24; ii < 4; ii++, shift -= 8 )
67          {
68              result[ ii ] = (byte) ( 0xFF & ( integer >> shift ) );
69          }
70          return result;
71      }
72  }
73