KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > com > maverick > crypto > asn1 > DERSequence


1 /*
2  * SSL-Explorer
3  *
4  * Copyright (C) 2003-2006 3SP LTD. All Rights Reserved
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version 2 of
9  * the License, or (at your option) any later version.
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public
16  * License along with this program; if not, write to the Free Software
17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18  */
19             
20 package com.maverick.crypto.asn1;
21
22 import java.io.ByteArrayOutputStream JavaDoc;
23 import java.io.IOException JavaDoc;
24 import java.util.Enumeration JavaDoc;
25
26 public class DERSequence
27     extends ASN1Sequence
28 {
29     /**
30      * create an empty sequence
31      */
32     public DERSequence()
33     {
34     }
35
36     /**
37      * create a sequence containing one object
38      */
39     public DERSequence(
40         DEREncodable obj)
41     {
42         this.addObject(obj);
43     }
44
45     /**
46      * create a sequence containing a vector of objects.
47      */
48     public DERSequence(
49         DEREncodableVector v)
50     {
51         for (int i = 0; i != v.size(); i++)
52         {
53             this.addObject(v.get(i));
54         }
55     }
56
57     /*
58      * A note on the implementation:
59      * <p>
60      * As DER requires the constructed, definite-length model to
61      * be used for structured types, this varies slightly from the
62      * ASN.1 descriptions given. Rather than just outputing SEQUENCE,
63      * we also have to specify CONSTRUCTED, and the objects length.
64      */
65     void encode(
66         DEROutputStream out)
67         throws IOException JavaDoc
68     {
69         ByteArrayOutputStream JavaDoc bOut = new ByteArrayOutputStream JavaDoc();
70         DEROutputStream dOut = new DEROutputStream(bOut);
71         Enumeration JavaDoc e = this.getObjects();
72
73         while (e.hasMoreElements())
74         {
75             Object JavaDoc obj = e.nextElement();
76
77             dOut.writeObject(obj);
78         }
79
80         dOut.close();
81
82         byte[] bytes = bOut.toByteArray();
83
84         out.writeEncoded(SEQUENCE | CONSTRUCTED, bytes);
85     }
86 }
87
Popular Tags