1 // Copyright 2000-2005 the Contributors, as shown in the revision logs.
2 // Licensed under the Apache Public Source License 2.0 ("the License").
3 // You may not use this file except in compliance with the License.
9 private static final byte[] encodingTable = {
10 (byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G',
11 (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N',
12 (byte)'O', (byte)'P', (byte)'Q', (byte)'R', (byte)'S', (byte)'T', (byte)'U',
13 (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z',
14 (byte)'a', (byte)'b', (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g',
15 (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m', (byte)'n',
16 (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u',
17 (byte)'v', (byte)'w', (byte)'x', (byte)'y', (byte)'z', (byte)'0', (byte)'1',
18 (byte)'2', (byte)'3', (byte)'4', (byte)'5', (byte)'6', (byte)'7', (byte)'8',
19 (byte)'9', (byte)'+', (byte)'/'
22 // FIXME could be far more efficient
23 public static class InputStream extends java.io.ByteArrayInputStream {
24 public InputStream(String s) { super(decode(s.getBytes())); }
28 * encode the input data producong a base 64 encoded byte array.
30 * @return a byte array containing the base 64 encoded data.
32 public static byte[] encode(byte[] data) {
35 int modulus = data.length % 3;
37 bytes = new byte[4 * data.length / 3];
39 bytes = new byte[4 * ((data.length / 3) + 1)];
42 int dataLength = (data.length - modulus);
44 for (int i = 0, j = 0; i < dataLength; i += 3, j += 4) {
46 a2 = data[i + 1] & 0xff;
47 a3 = data[i + 2] & 0xff;
49 bytes[j] = encodingTable[(a1 >>> 2) & 0x3f];
50 bytes[j + 1] = encodingTable[((a1 << 4) | (a2 >>> 4)) & 0x3f];
51 bytes[j + 2] = encodingTable[((a2 << 2) | (a3 >>> 6)) & 0x3f];
52 bytes[j + 3] = encodingTable[a3 & 0x3f];
59 case 0: /* nothing left to do */
62 d1 = data[data.length - 1] & 0xff;
63 b1 = (d1 >>> 2) & 0x3f;
64 b2 = (d1 << 4) & 0x3f;
66 bytes[bytes.length - 4] = encodingTable[b1];
67 bytes[bytes.length - 3] = encodingTable[b2];
68 bytes[bytes.length - 2] = (byte)'=';
69 bytes[bytes.length - 1] = (byte)'=';
72 d1 = data[data.length - 2] & 0xff;
73 d2 = data[data.length - 1] & 0xff;
75 b1 = (d1 >>> 2) & 0x3f;
76 b2 = ((d1 << 4) | (d2 >>> 4)) & 0x3f;
77 b3 = (d2 << 2) & 0x3f;
79 bytes[bytes.length - 4] = encodingTable[b1];
80 bytes[bytes.length - 3] = encodingTable[b2];
81 bytes[bytes.length - 2] = encodingTable[b3];
82 bytes[bytes.length - 1] = (byte)'=';
89 private static final byte[] decodingTable;
92 decodingTable = new byte[128];
93 for (int i = 'A'; i <= 'Z'; i++) decodingTable[i] = (byte)(i - 'A');
94 for (int i = 'a'; i <= 'z'; i++) decodingTable[i] = (byte)(i - 'a' + 26);
95 for (int i = '0'; i <= '9'; i++) decodingTable[i] = (byte)(i - '0' + 52);
96 decodingTable['+'] = 62;
97 decodingTable['/'] = 63;
101 * decode the base 64 encoded input data.
103 * @return a byte array representing the decoded data.
105 public static byte[] decode(byte[] data) {
109 if (data[data.length - 2] == '=') bytes = new byte[(((data.length / 4) - 1) * 3) + 1];
110 else if (data[data.length - 1] == '=') bytes = new byte[(((data.length / 4) - 1) * 3) + 2];
111 else bytes = new byte[((data.length / 4) * 3)];
113 for (int i = 0, j = 0; i < data.length - 4; i += 4, j += 3) {
114 b1 = decodingTable[data[i]];
115 b2 = decodingTable[data[i + 1]];
116 b3 = decodingTable[data[i + 2]];
117 b4 = decodingTable[data[i + 3]];
119 bytes[j] = (byte)((b1 << 2) | (b2 >> 4));
120 bytes[j + 1] = (byte)((b2 << 4) | (b3 >> 2));
121 bytes[j + 2] = (byte)((b3 << 6) | b4);
124 if (data[data.length - 2] == '=') {
125 b1 = decodingTable[data[data.length - 4]];
126 b2 = decodingTable[data[data.length - 3]];
127 bytes[bytes.length - 1] = (byte)((b1 << 2) | (b2 >> 4));
128 } else if (data[data.length - 1] == '=') {
129 b1 = decodingTable[data[data.length - 4]];
130 b2 = decodingTable[data[data.length - 3]];
131 b3 = decodingTable[data[data.length - 2]];
132 bytes[bytes.length - 2] = (byte)((b1 << 2) | (b2 >> 4));
133 bytes[bytes.length - 1] = (byte)((b2 << 4) | (b3 >> 2));
135 b1 = decodingTable[data[data.length - 4]];
136 b2 = decodingTable[data[data.length - 3]];
137 b3 = decodingTable[data[data.length - 2]];
138 b4 = decodingTable[data[data.length - 1]];
139 bytes[bytes.length - 3] = (byte)((b1 << 2) | (b2 >> 4));
140 bytes[bytes.length - 2] = (byte)((b2 << 4) | (b3 >> 2));
141 bytes[bytes.length - 1] = (byte)((b3 << 6) | b4);
147 * decode the base 64 encoded String data.
149 * @return a byte array representing the decoded data.
151 public static byte[] decode(String data) {
155 if (data.charAt(data.length() - 2) == '=')
156 bytes = new byte[(((data.length() / 4) - 1) * 3) + 1];
157 else if (data.charAt(data.length() - 1) == '=')
158 bytes = new byte[(((data.length() / 4) - 1) * 3) + 2];
160 bytes = new byte[((data.length() / 4) * 3)];
162 for (int i = 0, j = 0; i < data.length() - 4; i += 4, j += 3) {
163 b1 = decodingTable[data.charAt(i)];
164 b2 = decodingTable[data.charAt(i + 1)];
165 b3 = decodingTable[data.charAt(i + 2)];
166 b4 = decodingTable[data.charAt(i + 3)];
168 bytes[j] = (byte)((b1 << 2) | (b2 >> 4));
169 bytes[j + 1] = (byte)((b2 << 4) | (b3 >> 2));
170 bytes[j + 2] = (byte)((b3 << 6) | b4);
173 if (data.charAt(data.length() - 2) == '=') {
174 b1 = decodingTable[data.charAt(data.length() - 4)];
175 b2 = decodingTable[data.charAt(data.length() - 3)];
176 bytes[bytes.length - 1] = (byte)((b1 << 2) | (b2 >> 4));
177 } else if (data.charAt(data.length() - 1) == '=') {
178 b1 = decodingTable[data.charAt(data.length() - 4)];
179 b2 = decodingTable[data.charAt(data.length() - 3)];
180 b3 = decodingTable[data.charAt(data.length() - 2)];
181 bytes[bytes.length - 2] = (byte)((b1 << 2) | (b2 >> 4));
182 bytes[bytes.length - 1] = (byte)((b2 << 4) | (b3 >> 2));
184 b1 = decodingTable[data.charAt(data.length() - 4)];
185 b2 = decodingTable[data.charAt(data.length() - 3)];
186 b3 = decodingTable[data.charAt(data.length() - 2)];
187 b4 = decodingTable[data.charAt(data.length() - 1)];
188 bytes[bytes.length - 3] = (byte)((b1 << 2) | (b2 >> 4));
189 bytes[bytes.length - 2] = (byte)((b2 << 4) | (b3 >> 2));
190 bytes[bytes.length - 1] = (byte)((b3 << 6) | b4);