public void execute()

in lucene/src/main/java/com/twitter/elephantbird/lucene/HdfsMergeTool.java [62:101]

• 30 lines of code
• 3 McCabe index (conditional complexity)

  public void execute(Mapper.Context context) throws IOException {
    Configuration conf =  HadoopCompat.getConfiguration(context);

    List<String> indexes = HadoopUtils.readStringListFromConfAsBase64(INDEXES_KEY, conf);
    Path output = new Path(conf.get(OUTPUT_KEY));

    File tmpDirFile = Files.createTempDir();
    int maxMergeFactor = conf.getInt(MAX_MERGE_FACTOR_KEY, -1);
    Preconditions.checkArgument(maxMergeFactor > 0);

    Directory directory = new SimpleFSDirectory(tmpDirFile, NoLockFactory.getNoLockFactory());
    IndexWriter writer = LuceneIndexOutputFormat.createIndexWriter(
        directory,
        new LuceneIndexOutputFormat.NeverTokenizeAnalyzer(),
        maxMergeFactor);

    Directory[] dirs = new Directory[indexes.size()];
    int dir = 0;
    for (String index : indexes) {
      dirs[dir++] =  new LuceneHdfsDirectory(index, FileSystem.get(conf));
    }

    LOG.info("Adding indexes: " + indexes);
    writer.addIndexes(dirs);

    LOG.info("Force mergeing...");
    writer.forceMerge(1);

    LOG.info("Closing writer...");
    writer.close();


    FileSystem fs = FileSystem.get(conf);
    LOG.info("Copying index to HDFS...");
    if (!FileUtil.copy(tmpDirFile, fs, output, true, conf)) {
      throw new IOException("Failed to copy local index to HDFS!");
    }

    LOG.info("Index written to: " + output);
  }