An Example Of Using Exchanger

The following code is an exmple of using java.util.concurrent.Exchanger, The exchanger is a great way to swap data between threads.

package test;

import java.util.concurrent.Exchanger;
import java.util.concurrent.atomic.AtomicReference;

public class Main {

    public static void main(String[] args) {
        final Exchanger<Integer> e = new Exchanger<Integer>();
        new Thread(new Runnable() {

            private final AtomicReference<Integer> last = new AtomicReference<Integer>(1);

            @Override
            public void run() {
                try {
                    while (true) {
                        last.set(e.exchange(last.get()));
                        System.out.println("Thread A has value: " + last.get());
                        Thread.sleep(2000);
                    }
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }

        }).start();
        new Thread(new Runnable() {

            private final AtomicReference<Integer> last = new AtomicReference<Integer>(2);

            @Override
            public void run() {
                try {
                    while (true) {
                        last.set(e.exchange(last.get()));
                        System.out.println("Thread B has value: " + last.get());
                        Thread.sleep(2000);
                    }
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }

        }).start();
    }

}

written by Dhruba Bandopadhyay