I have a main client which keeps background timers for each peer. These timers run in a background thread, and in 30s (the timeout period) are scheduled to perform the task of marking the respective peer as offline. The block of code to do this is:

  public void startTimer() {
    timer = new Timer();
    timer.schedule(new TimerTask() {
      public void run() {
        status = false;
        System.out.println("Setting " + address.toString() + " status to offline");
        // need to send failure message somehow
        thread.sendMessage();
      }
    }, 5*1000);
  }

Then, in the main program, I need some way to detect when the above timer task has been run, so that the main client can then send a failure message to all other peers, something like:

while (true)
  if (msgFromThreadReceived)
     notifyPeers();

How would I be able to accomplish this with TimerTask? As I understand, the timer is running in a separate thread, and I want to somehow pass a message to the main thread to notify the main thread that the task has been run.