diff options
Diffstat (limited to 'libjava/classpath/java/util/zip/InflaterHuffmanTree.java')
| -rw-r--r-- | libjava/classpath/java/util/zip/InflaterHuffmanTree.java | 216 |
1 files changed, 108 insertions, 108 deletions
diff --git a/libjava/classpath/java/util/zip/InflaterHuffmanTree.java b/libjava/classpath/java/util/zip/InflaterHuffmanTree.java index 6c9b217..c12c732 100644 --- a/libjava/classpath/java/util/zip/InflaterHuffmanTree.java +++ b/libjava/classpath/java/util/zip/InflaterHuffmanTree.java @@ -40,37 +40,37 @@ package java.util.zip; class InflaterHuffmanTree { private static final int MAX_BITLEN = 15; - + private short[] tree; static InflaterHuffmanTree defLitLenTree, defDistTree; static { - try + try { - byte[] codeLengths = new byte[288]; - int i = 0; - while (i < 144) - codeLengths[i++] = 8; - while (i < 256) - codeLengths[i++] = 9; - while (i < 280) - codeLengths[i++] = 7; - while (i < 288) - codeLengths[i++] = 8; - defLitLenTree = new InflaterHuffmanTree(codeLengths); - - codeLengths = new byte[32]; - i = 0; - while (i < 32) - codeLengths[i++] = 5; - defDistTree = new InflaterHuffmanTree(codeLengths); - } + byte[] codeLengths = new byte[288]; + int i = 0; + while (i < 144) + codeLengths[i++] = 8; + while (i < 256) + codeLengths[i++] = 9; + while (i < 280) + codeLengths[i++] = 7; + while (i < 288) + codeLengths[i++] = 8; + defLitLenTree = new InflaterHuffmanTree(codeLengths); + + codeLengths = new byte[32]; + i = 0; + while (i < 32) + codeLengths[i++] = 5; + defDistTree = new InflaterHuffmanTree(codeLengths); + } catch (DataFormatException ex) { - throw new InternalError - ("InflaterHuffmanTree: static tree length illegal"); + throw new InternalError + ("InflaterHuffmanTree: static tree length illegal"); } } @@ -83,31 +83,31 @@ class InflaterHuffmanTree { buildTree(codeLengths); } - + private void buildTree(byte[] codeLengths) throws DataFormatException { int[] blCount = new int[MAX_BITLEN+1]; int[] nextCode = new int[MAX_BITLEN+1]; for (int i = 0; i < codeLengths.length; i++) { - int bits = codeLengths[i]; - if (bits > 0) - blCount[bits]++; + int bits = codeLengths[i]; + if (bits > 0) + blCount[bits]++; } int code = 0; int treeSize = 512; for (int bits = 1; bits <= MAX_BITLEN; bits++) { - nextCode[bits] = code; - code += blCount[bits] << (16 - bits); - if (bits >= 10) - { - /* We need an extra table for bit lengths >= 10. */ - int start = nextCode[bits] & 0x1ff80; - int end = code & 0x1ff80; - treeSize += (end - start) >> (16 - bits); - } + nextCode[bits] = code; + code += blCount[bits] << (16 - bits); + if (bits >= 10) + { + /* We need an extra table for bit lengths >= 10. */ + int start = nextCode[bits] & 0x1ff80; + int end = code & 0x1ff80; + treeSize += (end - start) >> (16 - bits); + } } if (code != 65536) throw new DataFormatException("Code lengths don't add up properly."); @@ -119,46 +119,46 @@ class InflaterHuffmanTree int treePtr = 512; for (int bits = MAX_BITLEN; bits >= 10; bits--) { - int end = code & 0x1ff80; - code -= blCount[bits] << (16 - bits); - int start = code & 0x1ff80; - for (int i = start; i < end; i += 1 << 7) - { - tree[DeflaterHuffman.bitReverse(i)] - = (short) ((-treePtr << 4) | bits); - treePtr += 1 << (bits-9); - } + int end = code & 0x1ff80; + code -= blCount[bits] << (16 - bits); + int start = code & 0x1ff80; + for (int i = start; i < end; i += 1 << 7) + { + tree[DeflaterHuffman.bitReverse(i)] + = (short) ((-treePtr << 4) | bits); + treePtr += 1 << (bits-9); + } } - + for (int i = 0; i < codeLengths.length; i++) { - int bits = codeLengths[i]; - if (bits == 0) - continue; - code = nextCode[bits]; - int revcode = DeflaterHuffman.bitReverse(code); - if (bits <= 9) - { - do - { - tree[revcode] = (short) ((i << 4) | bits); - revcode += 1 << bits; - } - while (revcode < 512); - } - else - { - int subTree = tree[revcode & 511]; - int treeLen = 1 << (subTree & 15); - subTree = -(subTree >> 4); - do - { - tree[subTree | (revcode >> 9)] = (short) ((i << 4) | bits); - revcode += 1 << bits; - } - while (revcode < treeLen); - } - nextCode[bits] = code + (1 << (16 - bits)); + int bits = codeLengths[i]; + if (bits == 0) + continue; + code = nextCode[bits]; + int revcode = DeflaterHuffman.bitReverse(code); + if (bits <= 9) + { + do + { + tree[revcode] = (short) ((i << 4) | bits); + revcode += 1 << bits; + } + while (revcode < 512); + } + else + { + int subTree = tree[revcode & 511]; + int treeLen = 1 << (subTree & 15); + subTree = -(subTree >> 4); + do + { + tree[subTree | (revcode >> 9)] = (short) ((i << 4) | bits); + revcode += 1 << bits; + } + while (revcode < treeLen); + } + nextCode[bits] = code + (1 << (16 - bits)); } } @@ -173,45 +173,45 @@ class InflaterHuffmanTree int lookahead, symbol; if ((lookahead = input.peekBits(9)) >= 0) { - if ((symbol = tree[lookahead]) >= 0) - { - input.dropBits(symbol & 15); - return symbol >> 4; - } - int subtree = -(symbol >> 4); - int bitlen = symbol & 15; - if ((lookahead = input.peekBits(bitlen)) >= 0) - { - symbol = tree[subtree | (lookahead >> 9)]; - input.dropBits(symbol & 15); - return symbol >> 4; - } - else - { - int bits = input.getAvailableBits(); - lookahead = input.peekBits(bits); - symbol = tree[subtree | (lookahead >> 9)]; - if ((symbol & 15) <= bits) - { - input.dropBits(symbol & 15); - return symbol >> 4; - } - else - return -1; - } + if ((symbol = tree[lookahead]) >= 0) + { + input.dropBits(symbol & 15); + return symbol >> 4; + } + int subtree = -(symbol >> 4); + int bitlen = symbol & 15; + if ((lookahead = input.peekBits(bitlen)) >= 0) + { + symbol = tree[subtree | (lookahead >> 9)]; + input.dropBits(symbol & 15); + return symbol >> 4; + } + else + { + int bits = input.getAvailableBits(); + lookahead = input.peekBits(bits); + symbol = tree[subtree | (lookahead >> 9)]; + if ((symbol & 15) <= bits) + { + input.dropBits(symbol & 15); + return symbol >> 4; + } + else + return -1; + } } else { - int bits = input.getAvailableBits(); - lookahead = input.peekBits(bits); - symbol = tree[lookahead]; - if (symbol >= 0 && (symbol & 15) <= bits) - { - input.dropBits(symbol & 15); - return symbol >> 4; - } - else - return -1; + int bits = input.getAvailableBits(); + lookahead = input.peekBits(bits); + symbol = tree[lookahead]; + if (symbol >= 0 && (symbol & 15) <= bits) + { + input.dropBits(symbol & 15); + return symbol >> 4; + } + else + return -1; } } } |