Review

class SegmentMerger {
  private final void mergeTerms() throws IOException {
    try {
      freqOutput = directory.createFile(segment + ".frq");
      proxOutput = directory.createFile(segment + ".prx");
      termInfosWriter =
              new TermInfosWriter(directory, segment, fieldInfos);
      skipInterval = termInfosWriter.skipInterval;
      queue = new SegmentMergeQueue(readers.size());

      mergeTermInfos();

    } finally {
      if (freqOutput != null) freqOutput.close();
      if (proxOutput != null) proxOutput.close();
      if (termInfosWriter != null) termInfosWriter.close();
      if (queue != null) queue.close();
    }
  }

}