Phaser Demo

PhaserDemo.java

package me.ellios.concurrency;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.Phaser;

/**
 * Author: ellios
 * Date: 12-8-14 Time: 下午5:03
 */
public class PhaserDemo {

    public static void main(String args[]) throws Exception {
        //
        final int count = 10;
        final int phaseToTerminate = 10;
        final Phaser phaser = new Phaser(count) {
            @Override
            protected boolean onAdvance(int phase, int registeredParties) {
                System.out.println();
                System.out.println("******************" + phase + "***********************");
                return phase == phaseToTerminate || registeredParties == 0;
            }
        };

        for(int i = 0; i < count; i++) {
            final Thread thread = new Thread(new Task(i, phaser));
            thread.start();
        }

        awaitPhase(phaser, phaseToTerminate);
        System.out.println("*******************done***********************");
    }

    public static class Task implements Runnable {
        //
        private final int id;
        private final Phaser phaser;

        public Task(int id, Phaser phaser) {
            this.id = id;
            this.phaser = phaser;
        }

        @Override
        public void run() {
            while(!phaser.isTerminated()) {
                System.out.print(id + ",");
                phaser.arriveAndAwaitAdvance();
            }
        }
    }

    public static void awaitPhase(Phaser phaser, int phase) {
        int p = phaser.register(); // assumes caller not already registered
        while (p <= phase) {
            if (phaser.isTerminated()) {
                break; // ... deal with unexpected termination
            } else {
                p = phaser.arriveAndAwaitAdvance();
            }
        }
        phaser.arriveAndDeregister();
    }
}