# Source code

    001/*
    002 *  Licensed to the Apache Software Foundation (ASF) under one or more
    003 *  contributor license agreements.  See the NOTICE file distributed with
    004 *  this work for additional information regarding copyright ownership.
    005 *  The ASF licenses this file to You under the Apache License, Version 2.0
    006 *  (the "License"); you may not use this file except in compliance with
    007 *  the License.  You may obtain a copy of the License at
    008 *
    009 *      http://www.apache.org/licenses/LICENSE-2.0
    010 *
    011 *  Unless required by applicable law or agreed to in writing, software
    012 *  distributed under the License is distributed on an "AS IS" BASIS,
    013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014 *  See the License for the specific language governing permissions and
    015 *  limitations under the License.
    016 *
    017 */
    018package org.apache.commons.compress.archivers.zip;
    019
    020
    021import org.apache.commons.compress.parallel.FileBasedScatterGatherBackingStore;
    022import org.apache.commons.compress.parallel.ScatterGatherBackingStore;
    023import org.apache.commons.compress.utils.BoundedInputStream;
    024
    025import java.io.Closeable;
    026import java.io.File;
    027import java.io.FileNotFoundException;
    028import java.io.IOException;
    029import java.io.InputStream;
    030import java.util.Queue;
    031import java.util.concurrent.ConcurrentLinkedQueue;
    032import java.util.zip.Deflater;
    033
    034/**
    035 * A zip output stream that is optimized for multi-threaded scatter/gather construction of zip files.
    036 * <p>
    037 * The internal data format of the entries used by this class are entirely private to this class
    038 * and are not part of any public api whatsoever.
    039 * </p>
    040 * <p>It is possible to extend this class to support different kinds of backing storage, the default
    041 * implementation only supports file-based backing.
    042 * </p>
    043 * Thread safety: This class supports multiple threads. But the "writeTo" method must be called
    044 * by the thread that originally created the {@link ZipArchiveEntry}.
    045 *
    046 * @since 1.10
    047 */
    048public class ScatterZipOutputStream implements Closeable {
    049    private final Queue<CompressedEntry> items = new ConcurrentLinkedQueue<>();
    050    private final ScatterGatherBackingStore backingStore;
    051    private final StreamCompressor streamCompressor;
    052
    053    private static class CompressedEntry {
    054        final ZipArchiveEntryRequest zipArchiveEntryRequest;
    055        final long crc;
    056        final long compressedSize;
    057        final long size;
    058
    059        public CompressedEntry(final ZipArchiveEntryRequest zipArchiveEntryRequest, final long crc, final long compressedSize, final long size) {
    060            this.zipArchiveEntryRequest = zipArchiveEntryRequest;
    061            this.crc = crc;
    062            this.compressedSize = compressedSize;
    063            this.size = size;
    064        }
    065
    066        /**
    067         * Update the original {@link ZipArchiveEntry} with sizes/crc
    068         * Do not use this methods from threads that did not create the instance itself !
    069         * @return the zipArchiveEntry that is basis for this request
    070         */
    071
    072        public ZipArchiveEntry transferToArchiveEntry(){
    073            final ZipArchiveEntry entry = zipArchiveEntryRequest.getZipArchiveEntry();
    074            entry.setCompressedSize(compressedSize);
    075            entry.setSize(size);
    076            entry.setCrc(crc);
    077            entry.setMethod(zipArchiveEntryRequest.getMethod());
    078            return entry;
    079        }
    080    }
    081
    082    public ScatterZipOutputStream(final ScatterGatherBackingStore backingStore,
    083                                  final StreamCompressor streamCompressor) {
    084        this.backingStore = backingStore;
    085        this.streamCompressor = streamCompressor;
    086    }
    087
    088    /**
    089     * Add an archive entry to this scatter stream.
    090     *
    091     * @param zipArchiveEntryRequest The entry to write.
    092     * @throws IOException    If writing fails
    093     */
    094    public void addArchiveEntry(final ZipArchiveEntryRequest zipArchiveEntryRequest) throws IOException {
    095        try (final InputStream payloadStream = zipArchiveEntryRequest.getPayloadStream()) {
    096            streamCompressor.deflate(payloadStream, zipArchiveEntryRequest.getMethod());
    097        }
    098        items.add(new CompressedEntry(zipArchiveEntryRequest, streamCompressor.getCrc32(),
    099                                      streamCompressor.getBytesWrittenForLastEntry(), streamCompressor.getBytesRead()));
    100    }
    101
    102    /**
    103     * Write the contents of this scatter stream to a target archive.
    104     *
    105     * @param target The archive to receive the contents of this {@link ScatterZipOutputStream}.
    106     * @throws IOException If writing fails
    107     */
    108    public void writeTo(final ZipArchiveOutputStream target) throws IOException {
    109        backingStore.closeForWriting();
    110        try (final InputStream data = backingStore.getInputStream()) {
    111            for (final CompressedEntry compressedEntry : items) {
    112                try (final BoundedInputStream rawStream = new BoundedInputStream(data,
    113                        compressedEntry.compressedSize)) {
    114                    target.addRawArchiveEntry(compressedEntry.transferToArchiveEntry(), rawStream);
    115                }
    116            }
    117        }
    118    }
    119
    120
    121    /**
    122     * Closes this stream, freeing all resources involved in the creation of this stream.
    123     * @throws IOException If closing fails
    124     */
    125    @Override
    126    public void close() throws IOException {
    127        backingStore.close();
    128        streamCompressor.close();
    129    }
    130
    131    /**
    132     * Create a {@link ScatterZipOutputStream} with default compression level that is backed by a file
    133     *
    134     * @param file The file to offload compressed data into.
    135     * @return A ScatterZipOutputStream that is ready for use.
    136     * @throws FileNotFoundException if the file cannot be found
    137     */
    138    public static ScatterZipOutputStream fileBased(final File file) throws FileNotFoundException {
    139        return fileBased(file, Deflater.DEFAULT_COMPRESSION);
    140    }
    141
    142    /**
    143     * Create a {@link ScatterZipOutputStream} that is backed by a file
    144     *
    145     * @param file             The file to offload compressed data into.
    146     * @param compressionLevel The compression level to use, @see #Deflater
    147     * @return A  ScatterZipOutputStream that is ready for use.
    148     * @throws FileNotFoundException if the file cannot be found
    149     */
    150    public static ScatterZipOutputStream fileBased(final File file, final int compressionLevel) throws FileNotFoundException {
    151        final ScatterGatherBackingStore bs = new FileBasedScatterGatherBackingStore(file);
    152        // lifecycle is bound to the ScatterZipOutputStream returned
    153        final StreamCompressor sc = StreamCompressor.create(compressionLevel, bs); //NOSONAR
    154        return new ScatterZipOutputStream(bs, sc);
    155    }
    156}