public class SimpleThreads {

  // Display a message, preceded by
  // the name of the current thread
  public static void threadMessage(String message) {
    String threadName =
      Thread.currentThread().getName();
    System.out.format("%s: %s%n",
              threadName,
              message);
  }  

  public static void main(String args[])
    throws InterruptedException {

    // Delay, in milliseconds before
    // we interrupt MessageLoop
    // thread (default one hour).
    long patience = 1000 * 60 * 60;

    // If command line argument
    // present, gives patience
    // in seconds.
    if (args.length > 0) {
      try {
        patience = Long.parseLong(args[0]) * 1000;
      } catch (NumberFormatException e) {
        System.err.println("Argument must be an integer.");
        System.exit(1);
      }
    }

    threadMessage("Starting MessageLoop thread");
    long startTime = System.currentTimeMillis();
    Thread t = new Thread(new MessageLoop());
    t.start();

    threadMessage("Waiting for MessageLoop thread to finish");
    // loop until MessageLoop
    // thread exits
    while (t.isAlive()) {
      threadMessage("Still waiting...");
      // Wait maximum of 1 second
      // for MessageLoop thread
      // to finish.
      t.join(1000);
      if (((System.currentTimeMillis() - startTime) > patience)
          && t.isAlive()) {
        threadMessage("Tired of waiting!");
        t.interrupt();
        // Shouldn't be long now
        // -- wait indefinitely
        t.join();
      }
    }
    threadMessage("Finally!");
  }
}