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package org.jaudiotagger.tag.vorbiscomment.util; |
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import org.jaudiotagger.audio.generic.Utils; |
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| 8 | 0 | public class Base64Coder |
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{ |
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| 11 | 3 | private static final char[] map1 = new char[64]; |
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static |
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{ |
| 15 | 3 | int i = 0; |
| 16 | 81 | for (char c = 'A'; c <= 'Z'; c++) |
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{ |
| 18 | 78 | map1[i++] = c; |
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} |
| 20 | 81 | for (char c = 'a'; c <= 'z'; c++) |
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{ |
| 22 | 78 | map1[i++] = c; |
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} |
| 24 | 33 | for (char c = '0'; c <= '9'; c++) |
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{ |
| 26 | 30 | map1[i++] = c; |
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} |
| 28 | 3 | map1[i++] = '+'; |
| 29 | 3 | map1[i++] = '/'; |
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} |
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| 33 | 3 | private static final byte[] map2 = new byte[128]; |
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static |
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{ |
| 37 | 387 | for (int i = 0; i < map2.length; i++) |
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{ |
| 39 | 384 | map2[i] = -1; |
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} |
| 41 | 195 | for (int i = 0; i < 64; i++) |
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{ |
| 43 | 192 | map2[map1[i]] = (byte) i; |
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} |
| 45 | 3 | } |
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public static String encode(final String s) |
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{ |
| 56 | 0 | return new String(encode(Utils.getDefaultBytes(s, "ISO-8859-1"))); |
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} |
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public static char[] encode(final byte[] in) |
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{ |
| 68 | 7 | final int iLen = in.length; |
| 69 | 7 | final int oDataLen = (iLen * 4 + 2) / 3; |
| 70 | 7 | final int oLen = ((iLen + 2) / 3) * 4; |
| 71 | 7 | final char[] out = new char[oLen]; |
| 72 | 7 | int ip = 0; |
| 73 | 7 | int op = 0; |
| 74 | 77118 | while (ip < iLen) |
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{ |
| 76 | 77111 | final int i0 = in[ip++] & 0xff; |
| 77 | 77111 | final int i1 = ip < iLen ? in[ip++] & 0xff : 0; |
| 78 | 77111 | final int i2 = ip < iLen ? in[ip++] & 0xff : 0; |
| 79 | 77111 | final int o0 = i0 >>> 2; |
| 80 | 77111 | final int o1 = ((i0 & 3) << 4) | (i1 >>> 4); |
| 81 | 77111 | final int o2 = ((i1 & 0xf) << 2) | (i2 >>> 6); |
| 82 | 77111 | final int o3 = i2 & 0x3F; |
| 83 | 77111 | out[op++] = map1[o0]; |
| 84 | 77111 | out[op++] = map1[o1]; |
| 85 | 77111 | out[op] = op < oDataLen ? map1[o2] : '='; |
| 86 | 77111 | op++; |
| 87 | 77111 | out[op] = op < oDataLen ? map1[o3] : '='; |
| 88 | 77111 | op++; |
| 89 | 77111 | } |
| 90 | 7 | return out; |
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} |
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public static String decode(final String s) |
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{ |
| 102 | 0 | return new String(decode(s.toCharArray())); |
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} |
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public static byte[] decode(final char[] in) |
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{ |
| 115 | 22 | int iLen = in.length; |
| 116 | 22 | if (iLen % 4 != 0) |
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{ |
| 118 | 0 | throw new IllegalArgumentException("Length of Base64 encoded input string is not a multiple of 4."); |
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} |
| 120 | 44 | while (iLen > 0 && in[iLen - 1] == '=') |
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{ |
| 122 | 22 | iLen--; |
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} |
| 124 | 22 | final int oLen = (iLen * 3) / 4; |
| 125 | 22 | final byte[] out = new byte[oLen]; |
| 126 | 22 | int ip = 0; |
| 127 | 22 | int op = 0; |
| 128 | 440559 | while (ip < iLen) |
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{ |
| 130 | 440537 | final int i0 = in[ip++]; |
| 131 | 440537 | final int i1 = in[ip++]; |
| 132 | 440537 | final int i2 = ip < iLen ? in[ip++] : 'A'; |
| 133 | 440537 | final int i3 = ip < iLen ? in[ip++] : 'A'; |
| 134 | 440537 | if (i0 > 127 || i1 > 127 || i2 > 127 || i3 > 127) |
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{ |
| 136 | 0 | throw new IllegalArgumentException("Illegal character in Base64 encoded data."); |
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} |
| 138 | 440537 | final int b0 = map2[i0]; |
| 139 | 440537 | final int b1 = map2[i1]; |
| 140 | 440537 | final int b2 = map2[i2]; |
| 141 | 440537 | final int b3 = map2[i3]; |
| 142 | 440537 | if (b0 < 0 || b1 < 0 || b2 < 0 || b3 < 0) |
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{ |
| 144 | 0 | throw new IllegalArgumentException("Illegal character in Base64 encoded data."); |
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} |
| 146 | 440537 | final int o0 = (b0 << 2) | (b1 >>> 4); |
| 147 | 440537 | final int o1 = ((b1 & 0xf) << 4) | (b2 >>> 2); |
| 148 | 440537 | final int o2 = ((b2 & 3) << 6) | b3; |
| 149 | 440537 | out[op++] = (byte) o0; |
| 150 | 440537 | if (op < oLen) |
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{ |
| 152 | 440537 | out[op++] = (byte) o1; |
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} |
| 154 | 440537 | if (op < oLen) |
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{ |
| 156 | 440515 | out[op++] = (byte) o2; |
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} |
| 158 | 440537 | } |
| 159 | 22 | return out; |
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} |
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} |