| /* |
| * Copyright (c) 1996, 2013, Oracle and/or its affiliates. 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.util.zip; |
| |
| import dalvik.annotation.optimization.ReachabilitySensitive; |
| import dalvik.system.CloseGuard; |
| |
| /** |
| * 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"; |
| * 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); |
| * compresser.end(); |
| * |
| * // 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 { |
| |
| // Android-added: @ReachabilitySensitive |
| // Finalization clears zsRef, and thus can't be allowed to occur early. |
| // Unlike some other CloseGuard uses, the spec allows clients to rely on finalization |
| // here. Thus dropping a deflater without calling close() should work correctly. |
| // It thus does not suffice to just rely on the CloseGuard annotation. |
| @ReachabilitySensitive |
| private final ZStreamRef zsRef; |
| private byte[] buf = new byte[0]; |
| private int off, len; |
| private int level, strategy; |
| private boolean setParams; |
| private boolean finish, finished; |
| private long bytesRead; |
| private long bytesWritten; |
| |
| // Android-changed: added close guard |
| @ReachabilitySensitive |
| private final CloseGuard guard = CloseGuard.get(); |
| |
| /** |
| * 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; |
| |
| /** |
| * Compression flush mode used to achieve best compression result. |
| * |
| * @see Deflater#deflate(byte[], int, int, int) |
| * @since 1.7 |
| */ |
| public static final int NO_FLUSH = 0; |
| |
| /** |
| * Compression flush mode used to flush out all pending output; may |
| * degrade compression for some compression algorithms. |
| * |
| * @see Deflater#deflate(byte[], int, int, int) |
| * @since 1.7 |
| */ |
| public static final int SYNC_FLUSH = 2; |
| |
| /** |
| * Compression flush mode used to flush out all pending output and |
| * reset the deflater. Using this mode too often can seriously degrade |
| * compression. |
| * |
| * @see Deflater#deflate(byte[], int, int, int) |
| * @since 1.7 |
| */ |
| public static final int FULL_FLUSH = 3; |
| |
| /** |
| * 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; |
| this.zsRef = new ZStreamRef(init(level, DEFAULT_STRATEGY, nowrap)); |
| // Android-changed: added close guard |
| guard.open("end"); |
| } |
| |
| /** |
| * 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 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(); |
| } |
| synchronized (zsRef) { |
| 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 void setDictionary(byte[] b, int off, int len) { |
| if (b == null) { |
| throw new NullPointerException(); |
| } |
| if (off < 0 || len < 0 || off > b.length - len) { |
| throw new ArrayIndexOutOfBoundsException(); |
| } |
| synchronized (zsRef) { |
| ensureOpen(); |
| setDictionary(zsRef.address(), 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. |
| * |
| * <p> If the compression strategy is changed, the next invocation |
| * of {@code deflate} will compress the input available so far with |
| * the old strategy (and may be flushed); the new strategy will take |
| * effect only after that invocation. |
| * |
| * @param strategy the new compression strategy |
| * @exception IllegalArgumentException if the compression strategy is |
| * invalid |
| */ |
| public void setStrategy(int strategy) { |
| switch (strategy) { |
| case DEFAULT_STRATEGY: |
| case FILTERED: |
| case HUFFMAN_ONLY: |
| break; |
| default: |
| throw new IllegalArgumentException(); |
| } |
| synchronized (zsRef) { |
| if (this.strategy != strategy) { |
| this.strategy = strategy; |
| setParams = true; |
| } |
| } |
| } |
| |
| /** |
| * Sets the compression level to the specified value. |
| * |
| * <p> If the compression level is changed, the next invocation |
| * of {@code deflate} will compress the input available so far |
| * with the old level (and may be flushed); the new level will |
| * take effect only after that invocation. |
| * |
| * @param level the new compression level (0-9) |
| * @exception IllegalArgumentException if the compression level is invalid |
| */ |
| public void setLevel(int level) { |
| if ((level < 0 || level > 9) && level != DEFAULT_COMPRESSION) { |
| throw new IllegalArgumentException("invalid compression level"); |
| } |
| synchronized (zsRef) { |
| 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() { |
| synchronized (zsRef) { |
| return len <= 0; |
| } |
| } |
| |
| /** |
| * When called, indicates that compression should end with the current |
| * contents of the input buffer. |
| */ |
| public void finish() { |
| synchronized (zsRef) { |
| 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 boolean finished() { |
| synchronized (zsRef) { |
| return finished; |
| } |
| } |
| |
| /** |
| * Compresses the input data and fills specified buffer with compressed |
| * data. Returns actual number of bytes of compressed data. A return value |
| * of 0 indicates that {@link #needsInput() needsInput} should be called |
| * in order to determine if more input data is required. |
| * |
| * <p>This method uses {@link #NO_FLUSH} as its compression flush mode. |
| * An invocation of this method of the form {@code deflater.deflate(b, off, len)} |
| * yields the same result as the invocation of |
| * {@code deflater.deflate(b, off, len, Deflater.NO_FLUSH)}. |
| * |
| * @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 written to the |
| * output buffer |
| */ |
| public int deflate(byte[] b, int off, int len) { |
| return deflate(b, off, len, NO_FLUSH); |
| } |
| |
| /** |
| * Compresses the input data and fills specified buffer with compressed |
| * data. Returns actual number of bytes of compressed data. A return value |
| * of 0 indicates that {@link #needsInput() needsInput} should be called |
| * in order to determine if more input data is required. |
| * |
| * <p>This method uses {@link #NO_FLUSH} as its compression flush mode. |
| * An invocation of this method of the form {@code deflater.deflate(b)} |
| * yields the same result as the invocation of |
| * {@code deflater.deflate(b, 0, b.length, Deflater.NO_FLUSH)}. |
| * |
| * @param b the buffer for the compressed data |
| * @return the actual number of bytes of compressed data written to the |
| * output buffer |
| */ |
| public int deflate(byte[] b) { |
| return deflate(b, 0, b.length, NO_FLUSH); |
| } |
| |
| /** |
| * Compresses the input data and fills the specified buffer with compressed |
| * data. Returns actual number of bytes of data compressed. |
| * |
| * <p>Compression flush mode is one of the following three modes: |
| * |
| * <ul> |
| * <li>{@link #NO_FLUSH}: allows the deflater to decide how much data |
| * to accumulate, before producing output, in order to achieve the best |
| * compression (should be used in normal use scenario). A return value |
| * of 0 in this flush mode indicates that {@link #needsInput()} should |
| * be called in order to determine if more input data is required. |
| * |
| * <li>{@link #SYNC_FLUSH}: all pending output in the deflater is flushed, |
| * to the specified output buffer, so that an inflater that works on |
| * compressed data can get all input data available so far (In particular |
| * the {@link #needsInput()} returns {@code true} after this invocation |
| * if enough output space is provided). Flushing with {@link #SYNC_FLUSH} |
| * may degrade compression for some compression algorithms and so it |
| * should be used only when necessary. |
| * |
| * <li>{@link #FULL_FLUSH}: all pending output is flushed out as with |
| * {@link #SYNC_FLUSH}. The compression state is reset so that the inflater |
| * that works on the compressed output data can restart from this point |
| * if previous compressed data has been damaged or if random access is |
| * desired. Using {@link #FULL_FLUSH} too often can seriously degrade |
| * compression. |
| * </ul> |
| * |
| * <p>In the case of {@link #FULL_FLUSH} or {@link #SYNC_FLUSH}, if |
| * the return value is {@code len}, the space available in output |
| * buffer {@code b}, this method should be invoked again with the same |
| * {@code flush} parameter and more output space. |
| * |
| * @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 |
| * @param flush the compression flush mode |
| * @return the actual number of bytes of compressed data written to |
| * the output buffer |
| * |
| * @throws IllegalArgumentException if the flush mode is invalid |
| * @since 1.7 |
| */ |
| public int deflate(byte[] b, int off, int len, int flush) { |
| if (b == null) { |
| throw new NullPointerException(); |
| } |
| if (off < 0 || len < 0 || off > b.length - len) { |
| throw new ArrayIndexOutOfBoundsException(); |
| } |
| synchronized (zsRef) { |
| ensureOpen(); |
| if (flush == NO_FLUSH || flush == SYNC_FLUSH || |
| flush == FULL_FLUSH) { |
| int thisLen = this.len; |
| int n = deflateBytes(zsRef.address(), b, off, len, flush); |
| bytesWritten += n; |
| bytesRead += (thisLen - this.len); |
| return n; |
| } |
| throw new IllegalArgumentException(); |
| } |
| } |
| |
| /** |
| * Returns the ADLER-32 value of the uncompressed data. |
| * @return the ADLER-32 value of the uncompressed data |
| */ |
| public int getAdler() { |
| synchronized (zsRef) { |
| ensureOpen(); |
| return getAdler(zsRef.address()); |
| } |
| } |
| |
| /** |
| * 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. |
| * |
| * @return the total (non-negative) number of uncompressed bytes input so far |
| * @since 1.5 |
| */ |
| public long getBytesRead() { |
| synchronized (zsRef) { |
| ensureOpen(); |
| return bytesRead; |
| } |
| } |
| |
| /** |
| * 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. |
| * |
| * @return the total (non-negative) number of compressed bytes output so far |
| * @since 1.5 |
| */ |
| public long getBytesWritten() { |
| synchronized (zsRef) { |
| ensureOpen(); |
| return bytesWritten; |
| } |
| } |
| |
| /** |
| * Resets deflater so that a new set of input data can be processed. |
| * Keeps current compression level and strategy settings. |
| */ |
| public void reset() { |
| synchronized (zsRef) { |
| ensureOpen(); |
| reset(zsRef.address()); |
| finish = false; |
| finished = false; |
| off = len = 0; |
| bytesRead = bytesWritten = 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 void end() { |
| synchronized (zsRef) { |
| // Android-changed: added close guard |
| guard.close(); |
| long addr = zsRef.address(); |
| zsRef.clear(); |
| if (addr != 0) { |
| end(addr); |
| buf = null; |
| } |
| } |
| } |
| |
| /** |
| * Closes the compressor when garbage is collected. |
| */ |
| protected void finalize() { |
| // Android-changed: added close guard |
| if (guard != null) { |
| guard.warnIfOpen(); |
| } |
| end(); |
| } |
| |
| private void ensureOpen() { |
| assert Thread.holdsLock(zsRef); |
| if (zsRef.address() == 0) |
| throw new NullPointerException("Deflater has been closed"); |
| } |
| |
| // Android-changed: initIDs handled in register method. |
| // private native static void initIDs(); |
| private native static long init(int level, int strategy, boolean nowrap); |
| private native static void setDictionary(long addr, byte[] b, int off, int len); |
| private native int deflateBytes(long addr, byte[] b, int off, int len, |
| int flush); |
| private native static int getAdler(long addr); |
| private native static void reset(long addr); |
| private native static void end(long addr); |
| } |