@VisibleForTesting
  static StreamExecutionEnvironment createStreamExecutionEnvironment(FlinkPipelineOptions options) {
    return createStreamExecutionEnvironment(
        options,
        MoreObjects.firstNonNull(options.getFilesToStage(), Collections.emptyList()),
        options.getFlinkConfDir());
  }
@Test
  public void shouldSetMaxParallelismStreaming() {
    FlinkPipelineOptions options = getDefaultPipelineOptions();
    options.setRunner(TestFlinkRunner.class);
    options.setMaxParallelism(42);

    StreamExecutionEnvironment sev =
        FlinkExecutionEnvironments.createStreamExecutionEnvironment(options);

    assertThat(options.getMaxParallelism(), is(42));
    assertThat(sev.getMaxParallelism(), is(42));
  }