gistfile1.java

  /**
   * An end to end test that writes some random files and ensures that when deflated separately, merged and inflated
   * they represent the same byte sequence as a concatenation of the original files.
   */
  @Test
  public void testParallelCompress() throws IOException {

    // generate the uncompressed files and create a merged version
    List<File> parts = Lists.newArrayList();
    for (int i = 0; i < NUMBER_PARTS; i++) {
      parts.add(randomFileOfSize(PART_SIZE_IN_BYTES));
    }
    File original = File.createTempFile("original-", ".txt", new File("/tmp/d2"));
    merge(parts, original);

    // compress each file separately, and add an extra file which will mark a close of the deflation stream
    List<File> deflated = Lists.newArrayList();
    for (File f : parts) {
      File compressedPart = File.createTempFile("comp-", D2Utils.fileExtension, new File("/tmp/d2"));
      D2Utils.compress(new FileInputStream(f), new FileOutputStream(compressedPart));
      deflated.add(compressedPart);
    }

    // merge and mergeAndDecompress
    File decompressed = File.createTempFile("inflated-", ".txt", new File("/tmp/d2"));
    D2Utils.decompress(inputStreamsToFiles(deflated), new FileOutputStream(decompressed));

    Assert.assertTrue("Content of files should be identical", FileUtils.contentEquals(original, decompressed));
  }