package wj;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* Created by wangjia .
* Date:2015/8/12 0012
* Time:16:58
*/
public class App {
static class NumberWrapper {
public int value = 1;
}
public static void main(String[] args) {
//初始化可重入锁
final Lock lock = new ReentrantLock();
//第一个条件当屏幕上输出到3
final Condition reachThreeCondition = lock.newCondition();
//第二个条件当屏幕上输出到6
final Condition reachSixCondition = lock.newCondition();
//NumberWrapper只是为了封装一个数字,一边可以将数字对象共享,并可以设置为final
//注意这里不要用Integer, Integer 是不可变对象
final NumberWrapper num = new NumberWrapper();
//初始化A线程
Thread threadA = new Thread(new Runnable() {
@Override
public void run() {
//需要先获得锁
lock.lock();
try {
System.out.println("threadA start write");
//A线程先输出前3个数
while (num.value <= 3) {
System.out.println(num.value);
num.value++;
}
//输出到3时要signal,告诉B线程可以开始了
reachThreeCondition.signal();
} finally {
lock.unlock();
}
lock.lock();
try {
//等待输出6的条件
reachSixCondition.await();
System.out.println("threadA start write");
//输出剩余数字
while (num.value <= 9) {
System.out.println(num.value);
num.value++;
}
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
}
});
Thread threadB = new Thread(new Runnable() {
@Override
public void run() {
try {
lock.lock();
while (num.value <= 3) {
//等待3输出完毕的信号
reachThreeCondition.await();
}
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
try {
lock.lock();
//已经收到信号,开始输出4,5,6
System.out.println("threadB start write");
while (num.value <= 6) {
System.out.println(num.value);
num.value++;
}
//4,5,6输出完毕,告诉A线程6输出完了
reachSixCondition.signal();
} finally {
lock.unlock();
}
}
});
//启动两个线程
threadB.start();
threadA.start();
}
}
/*out:
threadA start write
1
2
3
threadB start write
4
5
6
threadA start write
7
8
9
*/
原文:http://my.oschina.net/dadou/blog/491523