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Diffstat (limited to 'openjdk/java/util/zip/InflaterHuffmanTree.java')
| -rw-r--r-- | openjdk/java/util/zip/InflaterHuffmanTree.java | 220 |
1 files changed, 0 insertions, 220 deletions
diff --git a/openjdk/java/util/zip/InflaterHuffmanTree.java b/openjdk/java/util/zip/InflaterHuffmanTree.java deleted file mode 100644 index 1a152d2b..00000000 --- a/openjdk/java/util/zip/InflaterHuffmanTree.java +++ /dev/null @@ -1,220 +0,0 @@ -/* InflaterHuffmanTree.java -- - Copyright (C) 2001, 2004 Free Software Foundation, Inc. - -This file is part of GNU Classpath. - -GNU Classpath is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. - -GNU Classpath is distributed in the hope that it will be useful, but -WITHOUT ANY WARRANTY; without even the implied warranty of -MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU -General Public License for more details. - -You should have received a copy of the GNU General Public License -along with GNU Classpath; see the file COPYING. If not, write to the -Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA -02110-1301 USA. - -Linking this library statically or dynamically with other modules is -making a combined work based on this library. Thus, the terms and -conditions of the GNU General Public License cover the whole -combination. - -As a special exception, the copyright holders of this library give you -permission to link this library with independent modules to produce an -executable, regardless of the license terms of these independent -modules, and to copy and distribute the resulting executable under -terms of your choice, provided that you also meet, for each linked -independent module, the terms and conditions of the license of that -module. An independent module is a module which is not derived from -or based on this library. If you modify this library, you may extend -this exception to your version of the library, but you are not -obligated to do so. If you do not wish to do so, delete this -exception statement from your version. */ - -package java.util.zip; - -class InflaterHuffmanTree -{ - private static final int MAX_BITLEN = 15; - - private short[] tree; - - static InflaterHuffmanTree defLitLenTree, defDistTree; - - static - { - 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); - } - catch (DataFormatException ex) - { - throw new InternalError - ("InflaterHuffmanTree: static tree length illegal"); - } - } - - /** - * Constructs a Huffman tree from the array of code lengths. - * - * @param codeLengths the array of code lengths - */ - InflaterHuffmanTree(byte[] codeLengths) throws DataFormatException - { - 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 max = 0; - int code = 0; - int treeSize = 512; - for (int bits = 1; bits <= MAX_BITLEN; bits++) - { - nextCode[bits] = code; - if (blCount[bits] > 0) - max = bits; - 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 && max > 1) - throw new DataFormatException("incomplete dynamic bit lengths tree"); - - /* Now create and fill the extra tables from longest to shortest - * bit len. This way the sub trees will be aligned. - */ - tree = new short[treeSize]; - 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); - } - } - - 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)); - } - } - - /** - * Reads the next symbol from input. The symbol is encoded using the - * huffman tree. - * @param input the input source. - * @return the next symbol, or -1 if not enough input is available. - */ - int getSymbol(StreamManipulator input) throws DataFormatException - { - 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; - } - } - 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; - } - } -} |