[wait/notify/notifyAll] Example for Java Object's wait/notify/notifyAll #concurrency mechanism.

ObjectWaitNotifyExample.java

public class ObjectWaitNotifyExample {
    private static final long SLEEP_INTERVAL_MS = 1000;
    private boolean running = true;
    private Thread thread;

    public void start() {
        print("Inside start()...");
        thread = new Thread(new Runnable() {
            @Override
            public void run() {
                print("Inside run()...");
                try {
                    Thread.sleep(SLEEP_INTERVAL_MS);
                } catch (InterruptedException e) {
                    Thread.currentThread().interrupt();
                }
                synchronized (ObjectWaitNotifyExample.this) {
                    running = false;
                    ObjectWaitNotifyExample.this.notify();
                }
            }
        });
        thread.start();
    }

    public void join() throws InterruptedException {
        print("Inside join()...");
        synchronized (this) {
            while (running) {
                print("Waiting for the peer thread to finish.");
                wait();//waiting, not running
            }
            print("Peer thread finished.");
        }
    }

    private void print(String s) {
        System.out.println(s);
    }

    public static void main(String[] args) throws InterruptedException {
        ObjectWaitNotifyExample cve = new ObjectWaitNotifyExample();
        cve.start();
        cve.join();
    }
}