This example shows how to use notify() and wait() methods of Thread class.

Get the sources of the example from the following GitHub url : https://github.com/javaspringexamples/ThreadNotifyWait.git

Or Download a .zip file : https://github.com/javaspringexamples/ThreadNotifyWait/archive/master.zip

Thread-1 is waiting...
Thread-0: Says the field soccer is no more available.P1 please gets in my player and have fun.
Thread-3 is waiting...
P1 shoots ball 1
Thread-2 is waiting...
P1 shoots ball 2
P1 shoots ball 3
P1 shoots ball 4
P1 shoots ball 5
P1 shoots ball 6
P1 shoots ball 7
P1 shoots ball 8
P1 shoots ball 9
P1 shoots ball 10
Thread-0: Says the field soccer is available.
Dear threads get notified...!
Thread-1 is notified...
Thread-1: Says the field soccer is no more available.P2 please gets in my player and have fun.
P2 shoots ball 1
P2 shoots ball 2
P2 shoots ball 3
P2 shoots ball 4
P2 shoots ball 5
P2 shoots ball 6
P2 shoots ball 7
P2 shoots ball 8
P2 shoots ball 9
P2 shoots ball 10
Thread-1: Says the field soccer is available.
Dear threads get notified...!
Thread-3 is notified...
Thread-3: Says the field soccer is no more available.P4 please gets in my player and have fun.
P4 shoots ball 1
P4 shoots ball 2
P4 shoots ball 3
P4 shoots ball 4
P4 shoots ball 5
P4 shoots ball 6
P4 shoots ball 7
P4 shoots ball 8
P4 shoots ball 9
P4 shoots ball 10
Thread-3: Says the field soccer is available.
Dear threads get notified...!
Thread-2 is notified...
Thread-2: Says the field soccer is no more available.P3 please gets in my player and have fun.
P3 shoots ball 1
P3 shoots ball 2
P3 shoots ball 3
P3 shoots ball 4
P3 shoots ball 5
P3 shoots ball 6
P3 shoots ball 7
P3 shoots ball 8
P3 shoots ball 9
P3 shoots ball 10
Thread-2: Says the field soccer is available.
Dear threads get notified...!
All balls shooted.

package javaspringexamples.ThreadExamples;

/**
 * This example shows how to use notify() and wait() methods of Thread class.
 * 
 * @author mounir.sahrani@gmail.com
 *
 */
public class Player extends Thread {

	private String name;
	private SoccerField sf;

	public Player(String _name, SoccerField _sf) {
		name = _name;
		sf = _sf;
	}

	/**
	 * If the soccer field is available, then the player gets in to shoot balls.
	 */
	public void shootBalls() {
		sf.setAvailable(false);
		System.out.println(getName() + ": Says the field soccer is no more available." + name
				+ " please gets in my player and have fun.");
		for (int i = 1; i <= 10; i++)
			System.out.println(name + " shoots ball " + i);
		System.out.println(getName() + ": Says the field soccer is available.");
		sf.setAvailable(true);
	}

	@Override
	public void run() {
		sf.getSoccerField();
		shootBalls();
	}

	/**
	 * The main method.
	 */
	public static void main(String[] args) throws InterruptedException {
		SoccerField sf = new SoccerField();
		Player p1 = new Player("P1", sf);
		Player p2 = new Player("P2", sf);
		Player p3 = new Player("P3", sf);
		Player p4 = new Player("P4", sf);
		p1.start();
		p2.start();
		p3.start();
		p4.start();
		// Waiting for threads terminating their jobs.
		p1.join();
		p2.join();
		p3.join();
		p4.join();
		System.out.println("All balls shooted.");
	}
}

package javaspringexamples.ThreadExamples;

/**
 * This example shows how to use notify() and wait() methods of Thread class.
 * 
 * @author mounir.sahrani@gmail.com
 *
 */
public class SoccerField {
	private boolean available = true;

	/**
	 * If the soccer field is not available, then the thread will wait until
	 * being notified that the soccer field is available again.
	 */
	public synchronized void getSoccerField() {
		if (!available) {
			try {
				System.out.println(Thread.currentThread().getName() + " is waiting...");
				wait();
				System.out.println(Thread.currentThread().getName() + " is notified...");
			} catch (InterruptedException e) {
				// Do something to handle the InterruptedException
				e.printStackTrace();
			}
		}
	}

	/**
	 * When the soccer field is available, the other threads are notified to
	 * continue doing their jobs.
	 * 
	 */
	public synchronized void setAvailable(boolean a) {
		available = a;
		if (a) {
			notify();
			System.out.println("Dear threads get notified...!");
		}
	}

	public boolean isAvailable() {
		return available;
	}
}