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
020import org.apache.commons.compress.parallel.FileBasedScatterGatherBackingStore;
021import org.apache.commons.compress.parallel.InputStreamSupplier;
022import org.apache.commons.compress.parallel.ScatterGatherBackingStore;
023import org.apache.commons.compress.parallel.ScatterGatherBackingStoreSupplier;
024
025import java.io.File;
026import java.io.IOException;
027import java.util.ArrayList;
028import java.util.List;
029import java.util.concurrent.Callable;
030import java.util.concurrent.ExecutionException;
031import java.util.concurrent.ExecutorService;
032import java.util.concurrent.Executors;
033import java.util.concurrent.Future;
034import java.util.concurrent.TimeUnit;
035import java.util.concurrent.atomic.AtomicInteger;
036import java.util.zip.Deflater;
037
038import static java.util.Collections.synchronizedList;
039import static org.apache.commons.compress.archivers.zip.ZipArchiveEntryRequest.createZipArchiveEntryRequest;
040
041/**
042 * Creates a zip in parallel by using multiple threadlocal {@link ScatterZipOutputStream} instances.
043 * <p>
044 * Note that this class generally makes no guarantees about the order of things written to
045 * the output file. Things that need to come in a specific order (manifests, directories)
046 * must be handled by the client of this class, usually by writing these things to the
047 * {@link ZipArchiveOutputStream} <em>before</em> calling {@link #writeTo writeTo} on this class.</p>
048 * <p>
049 * The client can supply an {@link java.util.concurrent.ExecutorService}, but for reasons of
050 * memory model consistency, this will be shut down by this class prior to completion.
051 * </p>
052 * @since 1.10
053 */
054public class ParallelScatterZipCreator {
055    private final List<ScatterZipOutputStream> streams = synchronizedList(new ArrayList<ScatterZipOutputStream>());
056    private final ExecutorService es;
057    private final ScatterGatherBackingStoreSupplier backingStoreSupplier;
058    private final List<Future<Object>> futures = new ArrayList<Future<Object>>();
059
060    private final long startedAt = System.currentTimeMillis();
061    private long compressionDoneAt = 0;
062    private long scatterDoneAt;
063
064    private static class DefaultBackingStoreSupplier implements ScatterGatherBackingStoreSupplier {
065        final AtomicInteger storeNum = new AtomicInteger(0);
066
067        @Override
068        public ScatterGatherBackingStore get() throws IOException {
069            final File tempFile = File.createTempFile("parallelscatter", "n" + storeNum.incrementAndGet());
070            return new FileBasedScatterGatherBackingStore(tempFile);
071        }
072    }
073
074    private ScatterZipOutputStream createDeferred(final ScatterGatherBackingStoreSupplier scatterGatherBackingStoreSupplier)
075            throws IOException {
076        final ScatterGatherBackingStore bs = scatterGatherBackingStoreSupplier.get();
077        final StreamCompressor sc = StreamCompressor.create(Deflater.DEFAULT_COMPRESSION, bs);
078        return new ScatterZipOutputStream(bs, sc);
079    }
080
081    private final ThreadLocal<ScatterZipOutputStream> tlScatterStreams = new ThreadLocal<ScatterZipOutputStream>() {
082        @Override
083        protected ScatterZipOutputStream initialValue() {
084            try {
085                final ScatterZipOutputStream scatterStream = createDeferred(backingStoreSupplier);
086                streams.add(scatterStream);
087                return scatterStream;
088            } catch (final IOException e) {
089                throw new RuntimeException(e);
090            }
091        }
092    };
093
094    /**
095     * Create a ParallelScatterZipCreator with default threads, which is set to the number of available
096     * processors, as defined by {@link java.lang.Runtime#availableProcessors}
097     */
098    public ParallelScatterZipCreator() {
099        this(Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()));
100    }
101
102    /**
103     * Create a ParallelScatterZipCreator
104     *
105     * @param executorService The executorService to use for parallel scheduling. For technical reasons,
106     *                        this will be shut down by this class.
107     */
108    public ParallelScatterZipCreator(final ExecutorService executorService) {
109        this(executorService, new DefaultBackingStoreSupplier());
110    }
111
112    /**
113     * Create a ParallelScatterZipCreator
114     *
115     * @param executorService The executorService to use. For technical reasons, this will be shut down
116     *                        by this class.
117     * @param backingStoreSupplier The supplier of backing store which shall be used
118     */
119    public ParallelScatterZipCreator(final ExecutorService executorService,
120                                     final ScatterGatherBackingStoreSupplier backingStoreSupplier) {
121        this.backingStoreSupplier = backingStoreSupplier;
122        es = executorService;
123    }
124
125    /**
126     * Adds an archive entry to this archive.
127     * <p>
128     * This method is expected to be called from a single client thread
129     * </p>
130     *
131     * @param zipArchiveEntry The entry to add.
132     * @param source          The source input stream supplier
133     */
134
135    public void addArchiveEntry(final ZipArchiveEntry zipArchiveEntry, final InputStreamSupplier source) {
136        submit(createCallable(zipArchiveEntry, source));
137    }
138
139    /**
140     * Submit a callable for compression.
141     *
142     * @see ParallelScatterZipCreator#createCallable for details of if/when to use this.
143     *
144     * @param callable The callable to run, created by {@link #createCallable createCallable}, possibly wrapped by caller.
145     */
146    public final void submit(final Callable<Object> callable) {
147        futures.add(es.submit(callable));
148    }
149
150    /**
151     * Create a callable that will compress the given archive entry.
152     *
153     * <p>This method is expected to be called from a single client thread.</p>
154     *
155     * Consider using {@link #addArchiveEntry addArchiveEntry}, which wraps this method and {@link #submit submit}.
156     * The most common use case for using {@link #createCallable createCallable} and {@link #submit submit} from a
157     * client is if you want to wrap the callable in something that can be prioritized by the supplied
158     * {@link ExecutorService}, for instance to process large or slow files first.
159     * Since the creation of the {@link ExecutorService} is handled by the client, all of this is up to the client.
160     *
161     * @param zipArchiveEntry The entry to add.
162     * @param source          The source input stream supplier
163     * @return A callable that should subsequently passed to #submit, possibly in a wrapped/adapted from. The
164     * value of this callable is not used, but any exceptions happening inside the compression
165     * will be propagated through the callable.
166     */
167
168    public final Callable<Object> createCallable(final ZipArchiveEntry zipArchiveEntry, final InputStreamSupplier source) {
169        final int method = zipArchiveEntry.getMethod();
170        if (method == ZipMethod.UNKNOWN_CODE) {
171            throw new IllegalArgumentException("Method must be set on zipArchiveEntry: " + zipArchiveEntry);
172        }
173        final ZipArchiveEntryRequest zipArchiveEntryRequest = createZipArchiveEntryRequest(zipArchiveEntry, source);
174        return new Callable<Object>() {
175            @Override
176            public Object call() throws Exception {
177                tlScatterStreams.get().addArchiveEntry(zipArchiveEntryRequest);
178                return null;
179            }
180        };
181    }
182
183
184    /**
185     * Write the contents this to the target {@link ZipArchiveOutputStream}.
186     * <p>
187     * It may be beneficial to write things like directories and manifest files to the targetStream
188     * before calling this method.
189     * </p>
190     *
191     * @param targetStream The {@link ZipArchiveOutputStream} to receive the contents of the scatter streams
192     * @throws IOException          If writing fails
193     * @throws InterruptedException If we get interrupted
194     * @throws ExecutionException   If something happens in the parallel execution
195     */
196    public void writeTo(final ZipArchiveOutputStream targetStream)
197            throws IOException, InterruptedException, ExecutionException {
198
199        // Make sure we catch any exceptions from parallel phase
200        for (final Future<?> future : futures) {
201            future.get();
202        }
203
204        es.shutdown();
205        es.awaitTermination(1000 * 60, TimeUnit.SECONDS);  // == Infinity. We really *must* wait for this to complete
206
207        // It is important that all threads terminate before we go on, ensure happens-before relationship
208        compressionDoneAt = System.currentTimeMillis();
209
210        for (final ScatterZipOutputStream scatterStream : streams) {
211            scatterStream.writeTo(targetStream);
212            scatterStream.close();
213        }
214
215        scatterDoneAt = System.currentTimeMillis();
216    }
217
218    /**
219     * Returns a message describing the overall statistics of the compression run
220     *
221     * @return A string
222     */
223    public ScatterStatistics getStatisticsMessage() {
224        return new ScatterStatistics(compressionDoneAt - startedAt, scatterDoneAt - compressionDoneAt);
225    }
226}
227