/** Test using the gzip codec for reading */
 @Test
 public void testGzip() throws IOException {
   JobConf job = new JobConf(defaultConf);
   CompressionCodec gzip = new GzipCodec();
   ReflectionUtils.setConf(gzip, job);
   localFs.delete(workDir, true);
   writeFile(
       localFs,
       new Path(workDir, "part1.txt.gz"),
       gzip,
       "the quick\nbrown\nfox jumped\nover\n the lazy\n dog\n");
   writeFile(localFs, new Path(workDir, "part2.txt.gz"), gzip, "this is a test\nof gzip\n");
   FileInputFormat.setInputPaths(job, workDir);
   TextInputFormat format = new TextInputFormat();
   format.configure(job);
   InputSplit[] splits = format.getSplits(job, 100);
   assertEquals("compressed splits == 2", 2, splits.length);
   FileSplit tmp = (FileSplit) splits[0];
   if (tmp.getPath().getName().equals("part2.txt.gz")) {
     splits[0] = splits[1];
     splits[1] = tmp;
   }
   List<Text> results = readSplit(format, splits[0], job);
   assertEquals("splits[0] length", 6, results.size());
   assertEquals("splits[0][5]", " dog", results.get(5).toString());
   results = readSplit(format, splits[1], job);
   assertEquals("splits[1] length", 2, results.size());
   assertEquals("splits[1][0]", "this is a test", results.get(0).toString());
   assertEquals("splits[1][1]", "of gzip", results.get(1).toString());
 }
 /** Test using the gzip codec and an empty input file */
 @Test
 public void testGzipEmpty() throws IOException {
   JobConf job = new JobConf(defaultConf);
   CompressionCodec gzip = new GzipCodec();
   ReflectionUtils.setConf(gzip, job);
   localFs.delete(workDir, true);
   writeFile(localFs, new Path(workDir, "empty.gz"), gzip, "");
   FileInputFormat.setInputPaths(job, workDir);
   TextInputFormat format = new TextInputFormat();
   format.configure(job);
   InputSplit[] splits = format.getSplits(job, 100);
   assertEquals(
       "Compressed files of length 0 are not returned from FileInputFormat.getSplits().",
       1,
       splits.length);
   List<Text> results = readSplit(format, splits[0], job);
   assertEquals("Compressed empty file length == 0", 0, results.size());
 }
  @Test
  public void testFormat() throws Exception {
    JobConf job = new JobConf(defaultConf);
    Path file = new Path(workDir, "test.txt");

    // A reporter that does nothing
    Reporter reporter = Reporter.NULL;

    int seed = new Random().nextInt();
    LOG.info("seed = " + seed);
    Random random = new Random(seed);

    localFs.delete(workDir, true);
    FileInputFormat.setInputPaths(job, workDir);

    // for a variety of lengths
    for (int length = 0; length < MAX_LENGTH; length += random.nextInt(MAX_LENGTH / 10) + 1) {

      LOG.debug("creating; entries = " + length);

      // create a file with length entries
      Writer writer = new OutputStreamWriter(localFs.create(file));
      try {
        for (int i = 0; i < length; i++) {
          writer.write(Integer.toString(i));
          writer.write("\n");
        }
      } finally {
        writer.close();
      }

      // try splitting the file in a variety of sizes
      TextInputFormat format = new TextInputFormat();
      format.configure(job);
      LongWritable key = new LongWritable();
      Text value = new Text();
      for (int i = 0; i < 3; i++) {
        int numSplits = random.nextInt(MAX_LENGTH / 20) + 1;
        LOG.debug("splitting: requesting = " + numSplits);
        InputSplit[] splits = format.getSplits(job, numSplits);
        LOG.debug("splitting: got =        " + splits.length);

        if (length == 0) {
          assertEquals(
              "Files of length 0 are not returned from FileInputFormat.getSplits().",
              1,
              splits.length);
          assertEquals("Empty file length == 0", 0, splits[0].getLength());
        }

        // check each split
        BitSet bits = new BitSet(length);
        for (int j = 0; j < splits.length; j++) {
          LOG.debug("split[" + j + "]= " + splits[j]);
          RecordReader<LongWritable, Text> reader =
              format.getRecordReader(splits[j], job, reporter);
          try {
            int count = 0;
            while (reader.next(key, value)) {
              int v = Integer.parseInt(value.toString());
              LOG.debug("read " + v);
              if (bits.get(v)) {
                LOG.warn(
                    "conflict with " + v + " in split " + j + " at position " + reader.getPos());
              }
              assertFalse("Key in multiple partitions.", bits.get(v));
              bits.set(v);
              count++;
            }
            LOG.debug("splits[" + j + "]=" + splits[j] + " count=" + count);
          } finally {
            reader.close();
          }
        }
        assertEquals("Some keys in no partition.", length, bits.cardinality());
      }
    }
  }
  @Test
  public void testSplitableCodecs() throws IOException {
    JobConf conf = new JobConf(defaultConf);
    int seed = new Random().nextInt();
    // Create the codec
    CompressionCodec codec = null;
    try {
      codec =
          (CompressionCodec)
              ReflectionUtils.newInstance(
                  conf.getClassByName("org.apache.hadoop.io.compress.BZip2Codec"), conf);
    } catch (ClassNotFoundException cnfe) {
      throw new IOException("Illegal codec!");
    }
    Path file = new Path(workDir, "test" + codec.getDefaultExtension());

    // A reporter that does nothing
    Reporter reporter = Reporter.NULL;
    LOG.info("seed = " + seed);
    Random random = new Random(seed);
    FileSystem localFs = FileSystem.getLocal(conf);

    localFs.delete(workDir, true);
    FileInputFormat.setInputPaths(conf, workDir);

    final int MAX_LENGTH = 500000;

    // for a variety of lengths
    for (int length = MAX_LENGTH / 2;
        length < MAX_LENGTH;
        length += random.nextInt(MAX_LENGTH / 4) + 1) {

      LOG.info("creating; entries = " + length);

      // create a file with length entries
      Writer writer = new OutputStreamWriter(codec.createOutputStream(localFs.create(file)));
      try {
        for (int i = 0; i < length; i++) {
          writer.write(Integer.toString(i));
          writer.write("\n");
        }
      } finally {
        writer.close();
      }

      // try splitting the file in a variety of sizes
      TextInputFormat format = new TextInputFormat();
      format.configure(conf);
      LongWritable key = new LongWritable();
      Text value = new Text();
      for (int i = 0; i < 3; i++) {
        int numSplits = random.nextInt(MAX_LENGTH / 2000) + 1;
        LOG.info("splitting: requesting = " + numSplits);
        InputSplit[] splits = format.getSplits(conf, numSplits);
        LOG.info("splitting: got =        " + splits.length);

        // check each split
        BitSet bits = new BitSet(length);
        for (int j = 0; j < splits.length; j++) {
          LOG.debug("split[" + j + "]= " + splits[j]);
          RecordReader<LongWritable, Text> reader =
              format.getRecordReader(splits[j], conf, reporter);
          try {
            int counter = 0;
            while (reader.next(key, value)) {
              int v = Integer.parseInt(value.toString());
              LOG.debug("read " + v);

              if (bits.get(v)) {
                LOG.warn(
                    "conflict with " + v + " in split " + j + " at position " + reader.getPos());
              }
              assertFalse("Key in multiple partitions.", bits.get(v));
              bits.set(v);
              counter++;
            }
            if (counter > 0) {
              LOG.info("splits[" + j + "]=" + splits[j] + " count=" + counter);
            } else {
              LOG.debug("splits[" + j + "]=" + splits[j] + " count=" + counter);
            }
          } finally {
            reader.close();
          }
        }
        assertEquals("Some keys in no partition.", length, bits.cardinality());
      }
    }
  }