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POUsing threads to do multiple things without having a thread for each
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copied!<p>I have a class which basically does the same series of steps twice. Sounds like a perfect example of where to multithread your program. My question is though if I can do this with only two threads. Here is the general jist of things</p> <pre><code>Tester implements Runnable{ Thread obj1Thread, obj2Thread; MyObj obj1, obj2; String obj1Results, obj2Results; void runTests(){ obj1Thread = new Thread(this, "ob1 thread"); obj2Thread = new Thread(this, "ob2 thread"); obj1.start();//builds up obj1 obj2.start();//builds up obj2 if(obj1 and obj2 are finished building){ System.out.println(obj1); System.out.println(obj2); } obj1Thread.startSecondPhase()//runs a separate function that tests obj1 vs ob2. Essentially test(ob1, ob2) obj2Thread.startSecondPhase()//runs a separate function that tests obj2 vs ob1. Essentially test(ob2, ob1) if(obj1 and obj2 are finished testing){ System.out.println(obj1Results); System.out.println(obj2Results); } } } </code></pre> <p>I have gotten the first part - building up the objects - working. My questions are now - </p> <ol> <li>How can I get the main thread to wait for the two threads to finish their first part? Perhaps the main would do a <code>wait</code> on both objects and then after the threads <code>notifyAll</code> they do a wait on the main thread? But then how do the threads get a hold of the main thread? Perhaps with <code>this</code>?</li> <li>How can I have this 'second phase' of the run function without making a new class with a new thread and a new specific run function? I dont want to have to make a new class and everything for every little task.</li> </ol> <p>To clarify the sequence of events I want specifically is - </p> <ol> <li>Main thread initializes and starts two threads</li> <li>Both threads simultaneously build their respective objects</li> <li>When both threads finish building they pause. Then main thread prints the objects out in order.</li> <li>After main thread is done, the two threads continue their code to a testing phase simultaneously </li> <li>When the threads are done the main thread prints the results out. Could probably use a <code>join()</code> here</li> </ol> <p>Edit: Also, how can I tell the specific threads which objects I want them to work on? Right now Im doing it in a kinda hacky way (i'm working off the thread name). </p>

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