}

  @Override
  protected String getSuccessfulResult() {
    return RESULT_DATA;
  }

  private static final class ComposeFunction implements Function<Integer, String> {
    @Override
    public String apply(Integer input) {
      if (input.intValue() == VALID_INPUT_DATA) {
        return RESULT_DATA;
      } else {
        throw WRAPPED_EXCEPTION;
      }
    }
  }

  }

  @Override
  protected String getSuccessfulResult() {
    return RESULT_DATA;
  }

  private static final class ComposeFunction implements Function<Integer, String> {
    @Override
    public String apply(Integer input) {
      if (input.intValue() == VALID_INPUT_DATA) {
        return RESULT_DATA;
      } else {
        throw WRAPPED_EXCEPTION;
      }
    }
  }

  }

  @Override
  protected String getSuccessfulResult() {
    return RESULT_DATA;
  }

  private class ChainingFunction implements AsyncFunction<Integer, String> {
    @Override
    public ListenableFuture<String> apply(Integer input) throws Exception {
      switch (input) {
        case VALID_INPUT_DATA:
          outputFuture.set(RESULT_DATA);
          break;
        case SLOW_OUTPUT_VALID_INPUT_DATA:

  }

  @Override
  protected String getSuccessfulResult() {
    return RESULT_DATA;
  }

  private class ChainingFunction implements AsyncFunction<Integer, String> {
    @Override
    public ListenableFuture<String> apply(Integer input) throws Exception {
      switch (input) {
        case VALID_INPUT_DATA:
          outputFuture.set(RESULT_DATA);
          break;
        case SLOW_OUTPUT_VALID_INPUT_DATA:

     * @param resultData the result data to be processed
     * @return the processed result data after all ingesters have been applied
     */
    private ResultData ingest(final ResponseData responseData, final ResultData resultData) {
        if (ingestFactory == null) {
            return resultData;
        }
        ResultData target = resultData;

     *
     * @param target the result data to process
     * @param responseData the response data from crawling
     * @return the processed result data
     */
    public ResultData process(final ResultData target, final ResponseData responseData) {
        return target;
    }

    /**
     * Processes a document map for web/file crawling with access result.