A unit test for a contrived asynchronous example class

AsynchronousTaskTest.java

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import org.junit.Assert;
import org.junit.Test;

public class AsynchronousTaskTest implements Callback {
    
    private CountDownLatch latch;
    
    public void completed() {
        latch.countDown();
    }
    
    @Test
    public void testTask() throws InterruptedException {
        latch = new CountDownLatch(1);
        
        AsynchronousTask task = new AsynchronousTask(this);
        task.start();
        latch.await(10, TimeUnit.SECONDS);
        
        Assert.assertEquals(42, task.getResult());
    }
}