Source code: gnu/java/security/der/DERValue.java
1 /* DERValue.java -- a value read or written to a DER encoding.
2 Copyright (C) 2003 Free Software Foundation, Inc.
3
4 This file is part of GNU Classpath.
5
6 GNU Classpath is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10
11 GNU Classpath is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GNU Classpath; see the file COPYING. If not, write to the
18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 02110-1301 USA.
20
21 Linking this library statically or dynamically with other modules is
22 making a combined work based on this library. Thus, the terms and
23 conditions of the GNU General Public License cover the whole
24 combination.
25
26 As a special exception, the copyright holders of this library give you
27 permission to link this library with independent modules to produce an
28 executable, regardless of the license terms of these independent
29 modules, and to copy and distribute the resulting executable under
30 terms of your choice, provided that you also meet, for each linked
31 independent module, the terms and conditions of the license of that
32 module. An independent module is a module which is not derived from
33 or based on this library. If you modify this library, you may extend
34 this exception to your version of the library, but you are not
35 obligated to do so. If you do not wish to do so, delete this
36 exception statement from your version. */
37
38
39 package gnu.java.security.der;
40
41 import java.io.ByteArrayOutputStream;
42 import java.io.IOException;
43
44 public class DERValue implements DER
45 {
46
47 // Fields.
48 // ------------------------------------------------------------------------
49
50 private final int tagClass;
51 private final boolean constructed;
52 private final int tag;
53 private int length;
54 private final Object value;
55 private byte[] encoded;
56
57 // Constructor.
58 // ------------------------------------------------------------------------
59
60 public DERValue(int tag, int length, Object value, byte[] encoded)
61 {
62 tagClass = tag & 0xC0;
63 this.tag = tag & 0x1F;
64 constructed = (tag & CONSTRUCTED) == CONSTRUCTED;
65 this.length = length;
66 this.value = value;
67 if (encoded != null)
68 this.encoded = (byte[]) encoded.clone();
69 }
70
71 public DERValue(int tag, Object value)
72 {
73 this(tag, 0, value, null);
74 }
75
76 // Instance methods.
77 // ------------------------------------------------------------------------
78
79 public int getExternalTag()
80 {
81 return tagClass | tag | (constructed ? 0x20 : 0x00);
82 }
83
84 public int getTag()
85 {
86 return tag;
87 }
88
89 public int getTagClass()
90 {
91 return tagClass;
92 }
93
94 public boolean isConstructed()
95 {
96 return constructed;
97 }
98
99 public int getLength()
100 {
101 if (encoded == null)
102 {
103 try
104 {
105 ByteArrayOutputStream out = new ByteArrayOutputStream();
106 length = DERWriter.write(out, this);
107 encoded = out.toByteArray();
108 }
109 catch (IOException ioe)
110 {
111 encoded = new byte[0];
112 }
113 }
114 return length;
115 }
116
117 public Object getValue()
118 {
119 return value;
120 }
121
122 public Object getValueAs (final int derType) throws IOException
123 {
124 byte[] encoded = getEncoded ();
125 encoded[0] = (byte) derType;
126 return DERReader.read (encoded).getValue ();
127 }
128
129 public byte[] getEncoded()
130 {
131 if (encoded == null)
132 {
133 try
134 {
135 ByteArrayOutputStream out = new ByteArrayOutputStream();
136 length = DERWriter.write(out, this);
137 encoded = out.toByteArray();
138 }
139 catch (IOException ioe)
140 {
141 encoded = new byte[0];
142 }
143 }
144 return (byte[]) encoded.clone();
145 }
146
147 public int getEncodedLength()
148 {
149 if (encoded == null)
150 {
151 try
152 {
153 ByteArrayOutputStream out = new ByteArrayOutputStream();
154 length = DERWriter.write(out, this);
155 encoded = out.toByteArray();
156 }
157 catch (IOException ioe)
158 {
159 encoded = new byte[0];
160 }
161 }
162 return encoded.length;
163 }
164
165 public String toString()
166 {
167 return "DERValue [ tag=" + tag + ", class=" + tagClass + ", constructed="
168 + constructed + ", value=" + value + " ]";
169 }
170 }