DefaultBackingStoreSupplier.java

  1. /*
  2.  *  Licensed to the Apache Software Foundation (ASF) under one or more
  3.  *  contributor license agreements.  See the NOTICE file distributed with
  4.  *  this work for additional information regarding copyright ownership.
  5.  *  The ASF licenses this file to You under the Apache License, Version 2.0
  6.  *  (the "License"); you may not use this file except in compliance with
  7.  *  the License.  You may obtain a copy of the License at
  8.  *
  9.  *      http://www.apache.org/licenses/LICENSE-2.0
  10.  *
  11.  *  Unless required by applicable law or agreed to in writing, software
  12.  *  distributed under the License is distributed on an "AS IS" BASIS,
  13.  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14.  *  See the License for the specific language governing permissions and
  15.  *  limitations under the License.
  16.  */

  17. package org.apache.commons.compress.archivers.zip;

  18. import java.io.IOException;
  19. import java.nio.file.Files;
  20. import java.nio.file.Path;
  21. import java.util.concurrent.atomic.AtomicInteger;

  22. import org.apache.commons.compress.parallel.FileBasedScatterGatherBackingStore;
  23. import org.apache.commons.compress.parallel.ScatterGatherBackingStore;
  24. import org.apache.commons.compress.parallel.ScatterGatherBackingStoreSupplier;

  25. /**
  26.  * Implements {@link ScatterGatherBackingStoreSupplier} using a temporary folder.
  27.  * <p>
  28.  * For example:
  29.  * </p>
  30.  *
  31.  * <pre>
  32.  * final Path dir = Paths.get("target/custom-temp-dir");
  33.  * Files.createDirectories(dir);
  34.  * final ParallelScatterZipCreator zipCreator = new ParallelScatterZipCreator(Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()),
  35.  *         new DefaultBackingStoreSupplier(dir));
  36.  * </pre>
  37.  *
  38.  * @since 1.23
  39.  */
  40. public class DefaultBackingStoreSupplier implements ScatterGatherBackingStoreSupplier {

  41.     private static final String PREFIX = "parallelscatter";

  42.     private final AtomicInteger storeNum = new AtomicInteger();

  43.     private final Path dir;

  44.     /**
  45.      * Constructs a new instance. If {@code dir} is null, then use the default temporary-file directory.
  46.      *
  47.      * @param dir temporary folder, may be null, must exist if non-null.
  48.      */
  49.     public DefaultBackingStoreSupplier(final Path dir) {
  50.         this.dir = dir;
  51.     }

  52.     @Override
  53.     public ScatterGatherBackingStore get() throws IOException {
  54.         final String suffix = "n" + storeNum.incrementAndGet();
  55.         final Path tempFile = dir == null ? Files.createTempFile(PREFIX, suffix) : Files.createTempFile(dir, PREFIX, suffix);
  56.         return new FileBasedScatterGatherBackingStore(tempFile);
  57.     }
  58. }