Example of Wait-Notify synchronization in Java

SimpleWaitNotifyExample.java

class Bottle {
    private String message;

    Bottle() {
        message = "";
    }

    public synchronized void set(String message) {
        this.message = message;
        notifyAll();
    }

    public synchronized String get() {
        while (message.length() == 0) {
            try {
                wait();
            }
            catch (InterruptedException exception) {}
        }
        return message;
    }
}

class Producer implements Runnable {
    private Bottle bottle;

    Producer(Bottle bottle) {
        this.bottle = bottle;
    }

    public void run() {
        try {
            Thread.sleep(5000);
            bottle.set("hello");
        }
        catch (InterruptedException exception) {}
    }
}

class Consumer implements Runnable {
    private Bottle bottle;

    Consumer(Bottle bottle) {
        this.bottle = bottle;
    }

    public void run() {
        String message = bottle.get();
        System.out.format("Message in the bottle: %s %n", message);
    }
}

public class MessageWaiterDemo {
    public static void main(String[] args) {
        Bottle bottle = new Bottle();
        Thread producer = new Thread(new Producer(bottle));
        Thread consumer = new Thread(new Consumer(bottle));

        producer.start();
        consumer.start();

        try {
            producer.join();
            consumer.join();
        }
        catch (InterruptedException exception) {
            exception.printStackTrace();
        }
    }
}