使用多线程交替打印1--n，a进程打印1,4,7,……(3n+1),b进程打印2,7,10,……(3n+2),c进程打印3,6,9,……(3n)

涉及到多线程的同步，阻塞，wait,notify

代码如下

Num.java

public class Num {

private int num = 0;

public Num(int num) {

this.num = num;

}

public synchronized void printOne() {

try {

while (num%3!=1) {

this.wait();

}

System.out.println(Thread.currentThread().getName() + "------->"

+ (num++));

Thread.sleep(1000);

this.notifyAll();

} catch (Exception e) {

e.printStackTrace();

}

}

public synchronized void printTwo() {

try {

while (num%3!=2) {

this.wait();

}

System.out.println(Thread.currentThread().getName() + "------->"

+ (num++));

Thread.sleep(1000);

this.notifyAll();

} catch (Exception e) {

e.printStackTrace();

}

}

public synchronized void printThr() {

try {

while (num%3!=0) {

this.wait();

}

System.out.println(Thread.currentThread().getName() + "------->"

+ (num++));

Thread.sleep(1000);

this.notifyAll();

} catch (Exception e) {

e.printStackTrace();

}

}

} 三个线程类

public class PrintOne implements Runnable {

private Num num;

public PrintOne(Num num) {

this.num = num;

}

@Override

public void run() {

while (true) {

num.printOne();

}

}

}

public class PrintTwo implements Runnable {

private Num num;

public PrintTwo(Num num) {

this.num = num;

}

@Override

public void run() {

while (true) {

num.printTwo();

}

}

}

public class PrintThr implements Runnable {

private Num num;

public PrintThr(Num num) {

this.num = num;

}

@Override

public void run() {

while (true) {

num.printThr();

}

}

}

测试类

public class Test {

public static void main(String[] args) {

Num num = new Num(0);

Thread pOne = new Thread(new PrintOne(num));

Thread pTwo = new Thread(new PrintTwo(num));

Thread pThr = new Thread(new PrintThr(num));

pOne.setName("3n+1");

pTwo.setName("3n+2");

pThr.setName("3n ");

pOne.start();

pTwo.start();

pThr.start();

}

}

效果

3n ------->0

3n+1------->1

3n+2------->2

3n ------->3

3n+1------->4

3n+2------->5

…………