[FIXED] Wait for ExecutorChannel to finish in junit

Issue

I am using spring integration and junit.

@Test
public void testOnePojo() throws Exception {
    ExecutorChannel orderSendChannel = 
    context.getBean("validationChannel", ExecutorChannel.class);
    ExecutorChannel orderReceiveChannel = context.getBean("auditChannel", ExecutorChannel.class);
    orderReceiveChannel.subscribe(t -> {
         System.out.println(t);//I want to see this output     
    }); 
    orderSendChannel.send(getMessageMessage());
}

I cannot see the output from the receiving channel. JUnit exits after subscribing. It there a proper way to wait inside testOnePojo until auditChannel receives a response.

Solution

you can use a CoundDownLatch in your test and wait for the MessageHandler to handle your message. Your example would look something like this:

@Test
public void testOnePojo() throws Exception {
    final CountDownLatch countDownLatch = new CountDownLatch(1);

    ExecutorChannel orderSendChannel =
        context.getBean("validationChannel", ExecutorChannel.class);
    ExecutorChannel orderReceiveChannel = context.getBean("auditChannel", ExecutorChannel.class);
    orderReceiveChannel.subscribe(t -> {
        System.out.println(t);//I want to see this output
        countDownLatch.countDown();
    });
    orderSendChannel.send(getMessageMessage());

    countDownLatch.await();
}

Answered By - Yevgeniy
Answer Checked By - Marie Seifert (JavaFixing Admin)