java3个线程轮流输出1,2,3,4,5...75

原题描述

启动3个线程打印递增的数字, 线程1先打印1,2,3,4,5, 然后是线程2打印6,7,8,9,10, 然后是线程3打印11,12,13,14,15. 接着再由线程1打印16,17,18,19,20….以此类推, 直到打印到75. 

其实这里可以在每个线程中直接循环5次控制输出的结束，但是很多人对中断并不是很熟悉，所以我写成了中断的形式，希望可以加深对中断的理解。

而且这样更具通用性！

public class ProceedInsequence {
    private int no = 1;
    private final Lock lock = new ReentrantLock();
    private final Condition con1 = lock.newCondition();
    private final Condition con2 = lock.newCondition();
    private final Condition con3 = lock.newCondition();
    private int curNum = 1;

    private void printNum() {
        if (curNum > 75) {
            Thread.currentThread().interrupt();
            return;
        }
        for (int i = 0; i < 5; i++)
            System.out.println(Thread.currentThread().getName() + "  " + (curNum++));
    }

    public void process1() {
        lock.lock();
        try {
            while (no != 1)
                con1.await();
            printNum();
            no = 2;
            con2.signalAll();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }

    }

    public void process2() {
        lock.lock();
        try {
            while (no != 2)
                con2.await();
            printNum();
            no = 3;
            con3.signalAll();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

    public void process3() {
        lock.lock();
        try {
            while (no != 3) con3.await();
            printNum();
            no = 1;
            con1.signalAll();
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }
    }

    public static void main(String[] args) {
        final ProceedInsequence p = new ProceedInsequence();
        new Thread(() -> {
            while (!Thread.currentThread().isInterrupted())
                p.process1();
        }).start();

        new Thread(() -> {
            while (!Thread.currentThread().isInterrupted())
                p.process2();
        }).start();

        new Thread(() -> {
            while (!Thread.currentThread().isInterrupted())
                p.process3();
        }).start();

    }
}