package com.线程间通信;
import java.util.ArrayList;
import java.util.List;
public class Thread2Thread {
//声明一个 实例变量
private volatile static List<String> list = new ArrayList<String>();
public void add(){
list.add("1");
}
public int size(){
return list.size();
}
public static void main(String [] args){
final Thread2Thread t = new Thread2Thread();
final Object lock = new Object();
//线程1 往list中加数据
Thread t1 = new Thread(new Runnable() {
public void run() {
try {
synchronized(lock){
for (int i =0; i<10; i++){
t.add();
System.out.println("当前线程"+Thread.currentThread().getName()+":添加了一个数据。。");
Thread.sleep(500);
if(list.size() == 5){
//发送通知 但是notifi方法不释放锁 锁被释放是在10次循环结束后释放(即synchronized块结束后)
System.out.println("已经发出通知。。");
lock.notify();
}
}
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}, "t1");
//线程2 当list数组中有5个元素时 就打印一句话
Thread t2 = new Thread(new Runnable() {
public void run() {
synchronized(lock){
try {
if(t.size() != 5){
//wait释放锁 此时的线程就在这儿阻塞 所以下面的print语句没有打印 相反的t1线程获得了锁 也发出了通知
//这时 线程2就从阻塞状态中到active状态 于是就有了下面的打印 线程阻塞时 就让出了cpu,效率也提高了
lock.wait();
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//打印一句话
System.out.println("当前线程"+Thread.currentThread().getName()+":接收到通知。。");
throw new RuntimeException();
}
}
}, "t2");
t2.start();
t1.start();
}
}
转载请注明原文地址: https://ju.6miu.com/read-671157.html
