source: class RXToolTest {
  
      private Vertx vertx;
  
      @Test
      public void executeBlockingShouldFailSingleOnException() throws InterruptedException {
  
target:         CountDownLatch countDownLatch = new CountDownLatch(1);
          RXTool.executeBlocking(h -> {
              throw new RuntimeException("Expected");
          }, vertx)
              .subscribe(
                  v -> {
                      throw new RuntimeException("Should not be called");
                  },
                  t -> countDownLatch.countDown());
          countDownLatch.await(1, TimeUnit.SECONDS);
      }
  
  }