java 多线程同步的几种写法

package com.yangxiaochen;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.ForkJoinTask;
import java.util.concurrent.FutureTask;
import java.util.concurrent.Semaphore;

/**
 * @author yangxiaochen
 * @date 16/4/14 上午12:17
 */
public class ForkJoinTest {

public int m1() {
    try {
        Thread.sleep(5000);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
    System.out.println("m1");
    return 1;
}

public int m2() {
    try {
        Thread.sleep(5000);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
    System.out.println("m2");
    return 2;
}

public int m3() {
    try {
        Thread.sleep(5000);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
    System.out.println("m3");
    return 3;
}

    public static void main(String[] args) throws ExecutionException, InterruptedException {
        type0();
//        type1();
//        type2();
//        type3();
//        type4();

}

private static void type0() throws InterruptedException {
    ForkJoinTest test = new ForkJoinTest();
    class Holder {
        int a;
        int b;
        int c;
    }
    Holder h = new Holder();

Thread t1 = new Thread(() -> h.a = test.m1());
t1.start();

Thread t2 = new Thread(() -> h.b = test.m2());
t2.start();

Thread t3 = new Thread(() -> h.c = test.m3());
t3.start();

    t1.join();
    t2.join();
    t3.join();
    System.out.println(h.a + h.b + h.c);
}

private static void type4() throws InterruptedException {
    Semaphore semaphore = new Semaphore(0);

ForkJoinTest test = new ForkJoinTest();
class Holder {
    int a;
    int b;
    int c;
}
Holder h = new Holder();

new Thread(() -> {
    h.a = test.m1();
    semaphore.release();
}).start();

new Thread(() -> {
    h.b = test.m2();
    semaphore.release();
}).start();

new Thread(() -> {
    h.c = test.m3();
    semaphore.release();
}).start();

    semaphore.acquire(3);
    System.out.println(h.a + h.b + h.c);
}

private static void type3() throws InterruptedException {
    ForkJoinTest test = new ForkJoinTest();
    class Holder {
        int a;
        int b;
        int c;
    }
    Holder h = new Holder();

new Thread(() -> {
    h.a = test.m1();
    synchronized (test) {
        if (h.a != 0 && h.b != 0 && h.c != 0) {
            test.notify();
        }
    }
}).start();

new Thread(() -> {
    h.b = test.m2();
    synchronized (test) {
        if (h.a != 0 && h.b != 0 && h.c != 0) {
            test.notify();
        }
    }
}).start();

new Thread(() -> {
    h.c = test.m3();
    synchronized (test) {
        if (h.a != 0 && h.b != 0 && h.c != 0) {
            test.notify();
        }
    }
}).start();

synchronized (test) {
    test.wait();
}

    System.out.println(h.a + h.b + h.c);
}

private static void type2() throws InterruptedException, ExecutionException {
    ForkJoinTest test = new ForkJoinTest();

FutureTask<Integer> f1 = new FutureTask<>(() -> test.m1());
FutureTask<Integer> f2 = new FutureTask<>(() -> test.m2());
FutureTask<Integer> f3 = new FutureTask<>(() -> test.m3());

new Thread(f1).start();
new Thread(f2).start();
new Thread(f3).start();

    System.out.println(f1.get() + f2.get() + f3.get());
}

private static void type1() throws InterruptedException, ExecutionException {

ForkJoinTest test = new ForkJoinTest();

ForkJoinTask<Integer> f1 = ForkJoinTask.adapt(() -> test.m1()).fork();
ForkJoinTask<Integer> f2 = ForkJoinTask.adapt(() -> test.m2()).fork();
ForkJoinTask<Integer> f3 = ForkJoinTask.adapt(() -> test.m3()).fork();

        System.out.println(f1.join() + f2.join() + f3.join());
    }
}