Question

As in the title, I want to test a method like this:

public void startThread()
{
    new Thread()
    {
        public void run()
        {
            myLongProcess();
        }
    }.start();
}

EDIT:
Judging by comments I guess it is not very common to test if a thread starts or not. So I’ve to adjust the question… if my requirement is 100% code coverage do I need to test if that thread starts or not? If so do I really need an external framework?

Answer 1

This can be done elegantly with Mockito. Assuming the class is named ThreadLauncher you can ensure the startThread() method resulted in a call of myLongProcess() with:

public void testStart() throws Exception {
    // creates a decorator spying on the method calls of the real instance
    ThreadLauncher launcher = Mockito.spy(new ThreadLauncher());

    launcher.startThread();
    Thread.sleep(500);

    // verifies the myLongProcess() method was called
    Mockito.verify(launcher).myLongProcess();
}