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troubleshooting Question

Observer pattern with threads?

Avatar of DJ_AM_Juicebox
DJ_AM_Juicebox asked on
9 Comments1 Solution828 ViewsLast Modified:

How does the observer pattern work with two threads? For example, I have my main thread, then a background thread which needs to notify the main thread of some event. Something like:

public class MyApp implements INotify
     BackgroundThread m_thread;

     public MyApp()
         m_thread = new BackgroundThread(this);
     public void notifyMe(String str)
           System.out.println("Background thread says: " + str);

public class BackgroundThread implements Runnable
     INotify m_observer;

    public BackgroundThread(INotify observer)
        m_observer = observer;

    public void run()
         while (true) {
             Thread.Sleep(60 * 1000);

I must be using the wrong search terms because I can't find anything that shows how to do this, just large messaging APIs between remote servers and clients. But I just want to implement this within an application, so some classes can subscribe to a thread for message notifications. I've been searching for java + asynchronous notification etc.

Also, this needs to be j2me compliant which for me means java 1.3,

Avatar of Mick Barry
Mick BarryFlag of Australia imageJava Developer
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