Beispiel #1
0
  private void writeThenReadByRecordReader(
      int intervalRecordCount,
      int writeCount,
      int splitNumber,
      long minSplitSize,
      CompressionCodec codec)
      throws IOException {
    Path testDir =
        new Path(System.getProperty("test.data.dir", ".") + "/mapred/testsmallfirstsplit");
    Path testFile = new Path(testDir, "test_rcfile");
    fs.delete(testFile, true);
    Configuration cloneConf = new Configuration(conf);
    RCFileOutputFormat.setColumnNumber(cloneConf, bytesArray.length);
    cloneConf.setInt(RCFile.RECORD_INTERVAL_CONF_STR, intervalRecordCount);

    RCFile.Writer writer = new RCFile.Writer(fs, cloneConf, testFile, null, codec);

    BytesRefArrayWritable bytes = new BytesRefArrayWritable(bytesArray.length);
    for (int i = 0; i < bytesArray.length; i++) {
      BytesRefWritable cu = null;
      cu = new BytesRefWritable(bytesArray[i], 0, bytesArray[i].length);
      bytes.set(i, cu);
    }
    for (int i = 0; i < writeCount; i++) {
      if (i == intervalRecordCount) {
        System.out.println("write position:" + writer.getLength());
      }
      writer.append(bytes);
    }
    writer.close();

    RCFileInputFormat inputFormat = new RCFileInputFormat();
    JobConf jonconf = new JobConf(cloneConf);
    jonconf.set("mapred.input.dir", testDir.toString());
    jonconf.setLong("mapred.min.split.size", minSplitSize);
    InputSplit[] splits = inputFormat.getSplits(jonconf, splitNumber);
    assertEquals("splits length should be " + splitNumber, splits.length, splitNumber);
    int readCount = 0;
    for (int i = 0; i < splits.length; i++) {
      int previousReadCount = readCount;
      RecordReader rr = inputFormat.getRecordReader(splits[i], jonconf, Reporter.NULL);
      Object key = rr.createKey();
      Object value = rr.createValue();
      while (rr.next(key, value)) {
        readCount++;
      }
      System.out.println("The " + i + "th split read " + (readCount - previousReadCount));
    }
    assertEquals("readCount should be equal to writeCount", readCount, writeCount);
  }