--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/util/zip/Deflater.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,428 @@
+/*
+ * Copyright 1996-2006 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.util.zip;
+
+/**
+ * This class provides support for general purpose compression using the
+ * popular ZLIB compression library. The ZLIB compression library was
+ * initially developed as part of the PNG graphics standard and is not
+ * protected by patents. It is fully described in the specifications at
+ * the <a href="package-summary.html#package_description">java.util.zip
+ * package description</a>.
+ *
+ * <p>The following code fragment demonstrates a trivial compression
+ * and decompression of a string using <tt>Deflater</tt> and
+ * <tt>Inflater</tt>.
+ *
+ * <blockquote><pre>
+ * try {
+ * // Encode a String into bytes
+ * String inputString = "blahblahblah\u20AC\u20AC";
+ * byte[] input = inputString.getBytes("UTF-8");
+ *
+ * // Compress the bytes
+ * byte[] output = new byte[100];
+ * Deflater compresser = new Deflater();
+ * compresser.setInput(input);
+ * compresser.finish();
+ * int compressedDataLength = compresser.deflate(output);
+ *
+ * // Decompress the bytes
+ * Inflater decompresser = new Inflater();
+ * decompresser.setInput(output, 0, compressedDataLength);
+ * byte[] result = new byte[100];
+ * int resultLength = decompresser.inflate(result);
+ * decompresser.end();
+ *
+ * // Decode the bytes into a String
+ * String outputString = new String(result, 0, resultLength, "UTF-8");
+ * } catch(java.io.UnsupportedEncodingException ex) {
+ * // handle
+ * } catch (java.util.zip.DataFormatException ex) {
+ * // handle
+ * }
+ * </pre></blockquote>
+ *
+ * @see Inflater
+ * @author David Connelly
+ */
+public
+class Deflater {
+ private long strm;
+ private byte[] buf = new byte[0];
+ private int off, len;
+ private int level, strategy;
+ private boolean setParams;
+ private boolean finish, finished;
+
+ /**
+ * Compression method for the deflate algorithm (the only one currently
+ * supported).
+ */
+ public static final int DEFLATED = 8;
+
+ /**
+ * Compression level for no compression.
+ */
+ public static final int NO_COMPRESSION = 0;
+
+ /**
+ * Compression level for fastest compression.
+ */
+ public static final int BEST_SPEED = 1;
+
+ /**
+ * Compression level for best compression.
+ */
+ public static final int BEST_COMPRESSION = 9;
+
+ /**
+ * Default compression level.
+ */
+ public static final int DEFAULT_COMPRESSION = -1;
+
+ /**
+ * Compression strategy best used for data consisting mostly of small
+ * values with a somewhat random distribution. Forces more Huffman coding
+ * and less string matching.
+ */
+ public static final int FILTERED = 1;
+
+ /**
+ * Compression strategy for Huffman coding only.
+ */
+ public static final int HUFFMAN_ONLY = 2;
+
+ /**
+ * Default compression strategy.
+ */
+ public static final int DEFAULT_STRATEGY = 0;
+
+ static {
+ /* Zip library is loaded from System.initializeSystemClass */
+ initIDs();
+ }
+
+ /**
+ * Creates a new compressor using the specified compression level.
+ * If 'nowrap' is true then the ZLIB header and checksum fields will
+ * not be used in order to support the compression format used in
+ * both GZIP and PKZIP.
+ * @param level the compression level (0-9)
+ * @param nowrap if true then use GZIP compatible compression
+ */
+ public Deflater(int level, boolean nowrap) {
+ this.level = level;
+ this.strategy = DEFAULT_STRATEGY;
+ strm = init(level, DEFAULT_STRATEGY, nowrap);
+ }
+
+ /**
+ * Creates a new compressor using the specified compression level.
+ * Compressed data will be generated in ZLIB format.
+ * @param level the compression level (0-9)
+ */
+ public Deflater(int level) {
+ this(level, false);
+ }
+
+ /**
+ * Creates a new compressor with the default compression level.
+ * Compressed data will be generated in ZLIB format.
+ */
+ public Deflater() {
+ this(DEFAULT_COMPRESSION, false);
+ }
+
+ /**
+ * Sets input data for compression. This should be called whenever
+ * needsInput() returns true indicating that more input data is required.
+ * @param b the input data bytes
+ * @param off the start offset of the data
+ * @param len the length of the data
+ * @see Deflater#needsInput
+ */
+ public synchronized void setInput(byte[] b, int off, int len) {
+ if (b== null) {
+ throw new NullPointerException();
+ }
+ if (off < 0 || len < 0 || off > b.length - len) {
+ throw new ArrayIndexOutOfBoundsException();
+ }
+ this.buf = b;
+ this.off = off;
+ this.len = len;
+ }
+
+ /**
+ * Sets input data for compression. This should be called whenever
+ * needsInput() returns true indicating that more input data is required.
+ * @param b the input data bytes
+ * @see Deflater#needsInput
+ */
+ public void setInput(byte[] b) {
+ setInput(b, 0, b.length);
+ }
+
+ /**
+ * Sets preset dictionary for compression. A preset dictionary is used
+ * when the history buffer can be predetermined. When the data is later
+ * uncompressed with Inflater.inflate(), Inflater.getAdler() can be called
+ * in order to get the Adler-32 value of the dictionary required for
+ * decompression.
+ * @param b the dictionary data bytes
+ * @param off the start offset of the data
+ * @param len the length of the data
+ * @see Inflater#inflate
+ * @see Inflater#getAdler
+ */
+ public synchronized void setDictionary(byte[] b, int off, int len) {
+ if (strm == 0 || b == null) {
+ throw new NullPointerException();
+ }
+ if (off < 0 || len < 0 || off > b.length - len) {
+ throw new ArrayIndexOutOfBoundsException();
+ }
+ setDictionary(strm, b, off, len);
+ }
+
+ /**
+ * Sets preset dictionary for compression. A preset dictionary is used
+ * when the history buffer can be predetermined. When the data is later
+ * uncompressed with Inflater.inflate(), Inflater.getAdler() can be called
+ * in order to get the Adler-32 value of the dictionary required for
+ * decompression.
+ * @param b the dictionary data bytes
+ * @see Inflater#inflate
+ * @see Inflater#getAdler
+ */
+ public void setDictionary(byte[] b) {
+ setDictionary(b, 0, b.length);
+ }
+
+ /**
+ * Sets the compression strategy to the specified value.
+ * @param strategy the new compression strategy
+ * @exception IllegalArgumentException if the compression strategy is
+ * invalid
+ */
+ public synchronized void setStrategy(int strategy) {
+ switch (strategy) {
+ case DEFAULT_STRATEGY:
+ case FILTERED:
+ case HUFFMAN_ONLY:
+ break;
+ default:
+ throw new IllegalArgumentException();
+ }
+ if (this.strategy != strategy) {
+ this.strategy = strategy;
+ setParams = true;
+ }
+ }
+
+ /**
+ * Sets the current compression level to the specified value.
+ * @param level the new compression level (0-9)
+ * @exception IllegalArgumentException if the compression level is invalid
+ */
+ public synchronized void setLevel(int level) {
+ if ((level < 0 || level > 9) && level != DEFAULT_COMPRESSION) {
+ throw new IllegalArgumentException("invalid compression level");
+ }
+ if (this.level != level) {
+ this.level = level;
+ setParams = true;
+ }
+ }
+
+ /**
+ * Returns true if the input data buffer is empty and setInput()
+ * should be called in order to provide more input.
+ * @return true if the input data buffer is empty and setInput()
+ * should be called in order to provide more input
+ */
+ public boolean needsInput() {
+ return len <= 0;
+ }
+
+ /**
+ * When called, indicates that compression should end with the current
+ * contents of the input buffer.
+ */
+ public synchronized void finish() {
+ finish = true;
+ }
+
+ /**
+ * Returns true if the end of the compressed data output stream has
+ * been reached.
+ * @return true if the end of the compressed data output stream has
+ * been reached
+ */
+ public synchronized boolean finished() {
+ return finished;
+ }
+
+ /**
+ * Fills specified buffer with compressed data. Returns actual number
+ * of bytes of compressed data. A return value of 0 indicates that
+ * needsInput() should be called in order to determine if more input
+ * data is required.
+ * @param b the buffer for the compressed data
+ * @param off the start offset of the data
+ * @param len the maximum number of bytes of compressed data
+ * @return the actual number of bytes of compressed data
+ */
+ public synchronized int deflate(byte[] b, int off, int len) {
+ if (b == null) {
+ throw new NullPointerException();
+ }
+ if (off < 0 || len < 0 || off > b.length - len) {
+ throw new ArrayIndexOutOfBoundsException();
+ }
+ return deflateBytes(b, off, len);
+ }
+
+ /**
+ * Fills specified buffer with compressed data. Returns actual number
+ * of bytes of compressed data. A return value of 0 indicates that
+ * needsInput() should be called in order to determine if more input
+ * data is required.
+ * @param b the buffer for the compressed data
+ * @return the actual number of bytes of compressed data
+ */
+ public int deflate(byte[] b) {
+ return deflate(b, 0, b.length);
+ }
+
+ /**
+ * Returns the ADLER-32 value of the uncompressed data.
+ * @return the ADLER-32 value of the uncompressed data
+ */
+ public synchronized int getAdler() {
+ ensureOpen();
+ return getAdler(strm);
+ }
+
+ /**
+ * Returns the total number of uncompressed bytes input so far.
+ *
+ * <p>Since the number of bytes may be greater than
+ * Integer.MAX_VALUE, the {@link #getBytesRead()} method is now
+ * the preferred means of obtaining this information.</p>
+ *
+ * @return the total number of uncompressed bytes input so far
+ */
+ public int getTotalIn() {
+ return (int) getBytesRead();
+ }
+
+ /**
+ * Returns the total number of uncompressed bytes input so far.</p>
+ *
+ * @return the total (non-negative) number of uncompressed bytes input so far
+ * @since 1.5
+ */
+ public synchronized long getBytesRead() {
+ ensureOpen();
+ return getBytesRead(strm);
+ }
+
+ /**
+ * Returns the total number of compressed bytes output so far.
+ *
+ * <p>Since the number of bytes may be greater than
+ * Integer.MAX_VALUE, the {@link #getBytesWritten()} method is now
+ * the preferred means of obtaining this information.</p>
+ *
+ * @return the total number of compressed bytes output so far
+ */
+ public int getTotalOut() {
+ return (int) getBytesWritten();
+ }
+
+ /**
+ * Returns the total number of compressed bytes output so far.</p>
+ *
+ * @return the total (non-negative) number of compressed bytes output so far
+ * @since 1.5
+ */
+ public synchronized long getBytesWritten() {
+ ensureOpen();
+ return getBytesWritten(strm);
+ }
+
+ /**
+ * Resets deflater so that a new set of input data can be processed.
+ * Keeps current compression level and strategy settings.
+ */
+ public synchronized void reset() {
+ ensureOpen();
+ reset(strm);
+ finish = false;
+ finished = false;
+ off = len = 0;
+ }
+
+ /**
+ * Closes the compressor and discards any unprocessed input.
+ * This method should be called when the compressor is no longer
+ * being used, but will also be called automatically by the
+ * finalize() method. Once this method is called, the behavior
+ * of the Deflater object is undefined.
+ */
+ public synchronized void end() {
+ if (strm != 0) {
+ end(strm);
+ strm = 0;
+ buf = null;
+ }
+ }
+
+ /**
+ * Closes the compressor when garbage is collected.
+ */
+ protected void finalize() {
+ end();
+ }
+
+ private void ensureOpen() {
+ if (strm == 0)
+ throw new NullPointerException();
+ }
+
+ private static native void initIDs();
+ private native static long init(int level, int strategy, boolean nowrap);
+ private native static void setDictionary(long strm, byte[] b, int off,
+ int len);
+ private native int deflateBytes(byte[] b, int off, int len);
+ private native static int getAdler(long strm);
+ private native static long getBytesRead(long strm);
+ private native static long getBytesWritten(long strm);
+ private native static void reset(long strm);
+ private native static void end(long strm);
+}