使用Condition实现顺序执行

参考《Java多线程编程核心技术》

使用Condition对象可以对线程执行的业务进行排序规划

具体实现代码

public class Run2 {
    private static ReentrantLock lock = new ReentrantLock();
    private final static Condition conditionA = lock.newCondition();
    private final static Condition conditionB = lock.newCondition();
    private final static Condition conditionC = lock.newCondition();
    private volatile static int nextPrintWho = 1;
    public static void main(String[] args){
        Thread threadA = new Thread(){
            @Override
            public void run() {
                super.run();
                try {
                    lock.lock();
                    while (nextPrintWho != 1){
                        conditionA.await();
                    }
                    for (int i = 0; i < 3; i++) {
                        System.out.println("ThreadA "+ (i+1));
                    }
                    nextPrintWho = 2;
                    conditionB.signalAll();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                } finally {
                    lock.unlock();
                }
            }
        };

        Thread threadB = new Thread(){
            @Override
            public void run() {
                try {
                    lock.lock();
                    while (nextPrintWho !=2){
                        conditionB.await();
                    }
                    for (int i = 0; i < 3; i++) {
                        System.out.println("ThreadB "+(i+1));
                    }
                    nextPrintWho = 3;
                    conditionC.signalAll();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                } finally {
                    lock.unlock();
                }
            }
        };

        Thread threadC = new Thread(){
            @Override
            public void run() {
                try {
                    lock.lock();
                    while (nextPrintWho != 3){
                        conditionC.await();
                    }
                    for (int i = 0; i < 3; i++) {
                        System.out.println("ThreadC "+(i+1));
                    }
                    nextPrintWho = 1;
                    conditionA.signalAll();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                } finally {
                    lock.unlock();
                }
            }
        };

        Thread[] aArray = new Thread[5];
        Thread[] bArray = new Thread[5];
        Thread[] cArray = new Thread[5];

        for (int i = 0; i < 5; i++) {
            aArray[i] = new Thread(threadA);
            bArray[i] = new Thread(threadB);
            cArray[i] = new Thread(threadC);

            aArray[i].start();
            bArray[i].start();
            cArray[i].start();
        }
    }
}

-----------------------------------------------console---------------------------------------------------

ThreadA 1
ThreadA 2
ThreadA 3
ThreadB 1
ThreadB 2
ThreadB 3
ThreadC 1
ThreadC 2
ThreadC 3
ThreadA 1
ThreadA 2
ThreadA 3
ThreadB 1
ThreadB 2
ThreadB 3
ThreadC 1
ThreadC 2
ThreadC 3
ThreadA 1
ThreadA 2
ThreadA 3
ThreadB 1
ThreadB 2
ThreadB 3
ThreadC 1
ThreadC 2
ThreadC 3
ThreadA 1
ThreadA 2
ThreadA 3
ThreadB 1
ThreadB 2
ThreadB 3
ThreadC 1
ThreadC 2
ThreadC 3
ThreadA 1
ThreadA 2
ThreadA 3
ThreadB 1
ThreadB 2
ThreadB 3
ThreadC 1
ThreadC 2
ThreadC 3