@Test
  public void getThreadIds() {
    executorServiceRule.submit(() -> terminateLatch.await(TIMEOUT_MILLIS, MILLISECONDS));
    executorServiceRule.submit(() -> terminateLatch.await(TIMEOUT_MILLIS, MILLISECONDS));

    long[] threadIds = executorServiceRule.getThreadIds();
    assertThat(threadIds).hasSize(2);

    Set<Thread> threads = executorServiceRule.getThreads();
    for (Thread thread : threads) {
      assertThat(threadIds).contains(thread.getId());
    }
  }
Unit tests for {@link ExecutorServiceRule#getThreads()}.
geode-junit/src/test/java/org/apache/geode/test/junit/rules/ExecutorServiceRuleGetThreadsTest.java