/**
* @param args
*/
public static void main(String[] args) {
final Printer2 p = new Printer2();
new Thread() {
public void run() {
while(true) {
try {
p.print1();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}.start();
new Thread() {
public void run() {
while(true) {
try {
p.print2();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}.start();
new Thread() {
public void run() {
while(true) {
try {
p.print3();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}.start();
}
}
/*1,在同步代码块中,用哪个对象锁,就用哪个对象调用wait方法
* 2,为什么wait方法和notify方法定义在Object这类中?
* 因为锁对象可以是任意对象,Object是所有的类的基类,所以wait方法和notify方法需要定义在Object这个类中
* 3,sleep方法和wait方法的区别?
* a,sleep方法必须传入参数,参数就是时间,时间到了自动醒来
* wait方法可以传入参数也可以不传入参数,传入参数就是在参数的时间结束后等待,不传入参数就是直接等待
* b,sleep方法在同步函数或同步代码块中,不释放锁,睡着了也抱着锁睡
* wait方法在同步函数或者同步代码块中,释放锁
*/
class Printer2 {
private int flag = 1;
public void print1() throws InterruptedException {
synchronized(this) {
while(flag != 1) {
this.wait(); //当前线程等待
}
System.out.print("黑");
System.out.print("马");
System.out.print("程");
System.out.print("序");
System.out.print("员");
System.out.print("\r\n");
flag = 2;
//this.notify(); //随机唤醒单个等待的线程
this.notifyAll();
}
}
public void print2() throws InterruptedException {
synchronized(this) {
while(flag != 2) {
this.wait(); //线程2在此等待
}
System.out.print("传");
System.out.print("智");
System.out.print("播");
System.out.print("客");
System.out.print("\r\n");
flag = 3;
//this.notify();
this.notifyAll();
}
}
public void print3() throws InterruptedException {
synchronized(this) {
while(flag != 3) {
this.wait(); //线程3在此等待,if语句是在哪里等待,就在哪里起来
//while循环是循环判断,每次都会判断标记
}
System.out.print("i");
System.out.print("t");
System.out.print("h");
System.out.print("e");
System.out.print("i");
System.out.print("m");
System.out.print("a");
System.out.print("\r\n");
flag = 1;
//this.notify();
this.notifyAll();
}
}
原文:http://blog.51cto.com/357712148/2158223