diff options
author | upstream source tree <ports@midipix.org> | 2015-03-15 20:14:05 -0400 |
---|---|---|
committer | upstream source tree <ports@midipix.org> | 2015-03-15 20:14:05 -0400 |
commit | 554fd8c5195424bdbcabf5de30fdc183aba391bd (patch) | |
tree | 976dc5ab7fddf506dadce60ae936f43f58787092 /libjava/java/util/zip/Deflater.java | |
download | cbb-gcc-4.6.4-15d2061ac0796199866debe9ac87130894b0cdd3.tar.bz2 cbb-gcc-4.6.4-15d2061ac0796199866debe9ac87130894b0cdd3.tar.xz |
obtained gcc-4.6.4.tar.bz2 from upstream website;upstream
verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.
downloading a git-generated archive based on the 'upstream' tag
should provide you with a source tree that is binary identical
to the one extracted from the above tarball.
if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
directory might differ from line-endings of the respective
files in the upstream repository.
Diffstat (limited to 'libjava/java/util/zip/Deflater.java')
-rw-r--r-- | libjava/java/util/zip/Deflater.java | 354 |
1 files changed, 354 insertions, 0 deletions
diff --git a/libjava/java/util/zip/Deflater.java b/libjava/java/util/zip/Deflater.java new file mode 100644 index 000000000..47383ab4b --- /dev/null +++ b/libjava/java/util/zip/Deflater.java @@ -0,0 +1,354 @@ +/* Deflater.java - Compress a data stream + Copyright (C) 1999, 2000, 2001, 2004, 2006 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; + +import gnu.gcj.RawData; + +/** + * This is the Deflater class. The deflater class compresses input + * with the deflate algorithm described in RFC 1951. It has several + * compression levels and three different strategies described below. + * + * This class is <i>not</i> thread safe. This is inherent in the API, due + * to the split of deflate and setInput. + * + * @author Jochen Hoenicke + * @author Tom Tromey + */ +public class Deflater +{ + /** + * The best and slowest compression level. This tries to find very + * long and distant string repetitions. + */ + public static final int BEST_COMPRESSION = 9; + /** + * The worst but fastest compression level. + */ + public static final int BEST_SPEED = 1; + /** + * The default compression level. + */ + public static final int DEFAULT_COMPRESSION = -1; + /** + * This level won't compress at all but output uncompressed blocks. + */ + public static final int NO_COMPRESSION = 0; + + /** + * The default strategy. + */ + public static final int DEFAULT_STRATEGY = 0; + /** + * This strategy will only allow longer string repetitions. It is + * useful for random data with a small character set. + */ + public static final int FILTERED = 1; + + /** + * This strategy will not look for string repetitions at all. It + * only encodes with Huffman trees (which means, that more common + * characters get a smaller encoding. + */ + public static final int HUFFMAN_ONLY = 2; + + /** + * The compression method. This is the only method supported so far. + * There is no need to use this constant at all. + */ + public static final int DEFLATED = 8; + + /** Compression level. */ + private int level; + + /** Compression strategy. */ + private int strategy; + + /** The zlib stream. */ + private RawData zstream; + + /** True if finished. */ + private boolean is_finished; + + /** `Flush' flag to pass to next call to deflate. */ + private int flush_flag; + + /** + * Creates a new deflater with default compression level. + */ + public Deflater() + { + this(DEFAULT_COMPRESSION, false); + } + + /** + * Creates a new deflater with given compression level. + * @param lvl the compression level, a value between NO_COMPRESSION + * and BEST_COMPRESSION, or DEFAULT_COMPRESSION. + * @exception IllegalArgumentException if lvl is out of range. + */ + public Deflater(int lvl) + { + this(lvl, false); + } + + /** + * Creates a new deflater with given compression level. + * @param lvl the compression level, a value between NO_COMPRESSION + * and BEST_COMPRESSION. + * @param nowrap true, iff we should suppress the deflate header at the + * beginning and the adler checksum at the end of the output. This is + * useful for the GZIP format. + * @exception IllegalArgumentException if lvl is out of range. + */ + public Deflater(int lvl, boolean noHeader) + { + this.strategy = DEFAULT_STRATEGY; + init(lvl, noHeader); + setLevel(lvl); + } + + private native void init(int level, boolean noHeader); + + private native void update(); + + /** + * Resets the deflater. The deflater acts afterwards as if it was + * just created with the same compression level and strategy as it + * had before. + */ + public native void reset(); + + /** + * Frees all objects allocated by the compressor. There's no + * reason to call this, since you can just rely on garbage + * collection. Exists only for compatibility against Sun's JDK, + * where the compressor allocates native memory. + * If you call any method (even reset) afterwards the behaviour is + * <i>undefined</i>. + * @deprecated Just clear all references to deflater instead. + */ + public native void end(); + + /** + * Gets the current adler checksum of the data that was processed so + * far. + */ + public native int getAdler(); + + /** + * Gets the number of input bytes processed so far. + */ + @Deprecated + public int getTotalIn() + { + return (int) getBytesRead(); + } + + /** + * Gets the number of input bytes processed so far. + * @since 1.5 + */ + public native long getBytesRead(); + + /** + * Gets the number of output bytes so far. + */ + @Deprecated + public int getTotalOut() + { + return (int) getBytesWritten(); + } + + /** + * Gets the number of output bytes so far. + * @since 1.5 + */ + public native long getBytesWritten(); + + /** + * Finalizes this object. + */ + protected void finalize() + { + end(); + } + + /** + * Finishes the deflater with the current input block. It is an error + * to give more input after this method was called. This method must + * be called to force all bytes to be flushed. + */ + public native void finish(); + + /** + * Returns true iff the stream was finished and no more output bytes + * are available. + */ + public synchronized boolean finished() + { + return is_finished; + } + + /** + * Returns true, if the input buffer is empty. + * You should then call setInput(). <br> + * + * <em>NOTE</em>: This method can also return true when the stream + * was finished. + */ + public native boolean needsInput(); + + /** + * Sets the data which should be compressed next. This should be only + * called when needsInput indicates that more input is needed. + * If you call setInput when needsInput() returns false, the + * previous input that is still pending will be thrown away. + * The given byte array should not be changed, before needsInput() returns + * true again. + * This call is equivalent to <code>setInput(input, 0, input.length)</code>. + * @param input the buffer containing the input data. + * @exception IllegalStateException if the buffer was finished() or ended(). + */ + public void setInput(byte[] input) + { + setInput(input, 0, input.length); + } + + /** + * Sets the data which should be compressed next. This should be + * only called when needsInput indicates that more input is needed. + * The given byte array should not be changed, before needsInput() returns + * true again. + * @param input the buffer containing the input data. + * @param off the start of the data. + * @param len the length of the data. + * @exception IllegalStateException if the buffer was finished() or ended() + * or if previous input is still pending. + */ + public native void setInput(byte[] input, int off, int len); + + /** + * Sets the compression level. There is no guarantee of the exact + * position of the change, but if you call this when needsInput is + * true the change of compression level will occur somewhere near + * before the end of the so far given input. + * @param lvl the new compression level. + */ + public synchronized void setLevel(int lvl) + { + if (lvl != -1 && (lvl < 0 || lvl > 9)) + throw new IllegalArgumentException(); + level = (lvl == -1) ? 6 : lvl; + update(); + } + + /** + * Sets the compression strategy. Strategy is one of + * DEFAULT_STRATEGY, HUFFMAN_ONLY and FILTERED. For the exact + * position where the strategy is changed, the same as for + * setLevel() applies. + * @param stgy the new compression strategy. + */ + public synchronized void setStrategy(int stgy) + { + if (stgy != DEFAULT_STRATEGY && stgy != FILTERED + && stgy != HUFFMAN_ONLY) + throw new IllegalArgumentException(); + strategy = stgy; + update(); + } + + /** + * Deflates the current input block to the given array. It returns + * the number of bytes compressed, or 0 if either + * needsInput() or finished() returns true or length is zero. + * @param output the buffer where to write the compressed data. + */ + public int deflate(byte[] output) + { + return deflate(output, 0, output.length); + } + + /** + * Deflates the current input block to the given array. It returns + * the number of bytes compressed, or 0 if either + * needsInput() or finished() returns true or length is zero. + * @param output the buffer where to write the compressed data. + * @param offset the offset into the output array. + * @param length the maximum number of bytes that may be written. + * @exception IllegalStateException if end() was called. + * @exception IndexOutOfBoundsException if offset and/or length + * don't match the array length. + */ + public native int deflate(byte[] output, int off, int len); + + /** + * Sets the dictionary which should be used in the deflate process. + * This call is equivalent to <code>setDictionary(dict, 0, + * dict.length)</code>. + * @param dict the dictionary. + * @exception IllegalStateException if setInput () or deflate () + * were already called or another dictionary was already set. + */ + public void setDictionary(byte[] dict) + { + setDictionary(dict, 0, dict.length); + } + + /** + * Sets the dictionary which should be used in the deflate process. + * The dictionary should be a byte array containing strings that are + * likely to occur in the data which should be compressed. The + * dictionary is not stored in the compressed output, only a + * checksum. To decompress the output you need to supply the same + * dictionary again. + * @param dict the dictionary. + * @param offset an offset into the dictionary. + * @param length the length of the dictionary. + * @exception IllegalStateException if setInput () or deflate () were + * already called or another dictionary was already set. + */ + public native void setDictionary(byte[] buf, int off, int len); + + // Classpath's compression library supports flushing, but we + // don't. So this is a no-op here. + void flush() + { + } +} |