Using an instance of a java.util.concurrent.CountDownLatch, we can wait for a latch to count down to zero, blocking the calling thread before continuing. When passing in a timeout, the method returns true if the count reached zero or false if the timeout expires.

To make the timeout more explicit, the CountDownLatchWithTimeout class will throw a TimeoutException rather than force you to check. Using a static import, the example looks like the following.

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private final CountDownLatch startup = new CountDownLatch(1);

public void waitForStartup() throws InterruptedException, TimeoutException {
    await(startup).with(TIMEOUT);
}

The use of the with method is required. Following the micro- DSL approach, it is the with that actually does the waiting. Calling the await method on it's own will not block.

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