首页 > 代码库 > Java notify的使用

Java notify的使用

2024-07-24 18:02:11   216人阅读

半路出家学习java, 花了几分钟简单看了。在早上那个例子上稍微改了下，

我的理解是在java synchronized只是个线程同步标志，但是不会堵塞线程，而wait会堵塞调用者线程，类windows的堵塞函数，而notify相当于解锁（个人把这个过程当临界区来理解的），下边例子主要是，默认先运行的线程test1会先执行， 我稍微改了下， 让第一个线程挂起，等第二个线程执行完，再执行第一个线程

代码

import java.util.concurrent.CountDownLatch;public class CountDown {	private static CountDownLatch connectedSignal = new CountDownLatch(50);	static class MyThread implements Runnable {		public void run() {			Thread current = Thread.currentThread();			System.out.println(current.getName());						synchronized (connectedSignal) {				Thread thread = Thread.currentThread();				String name = thread.getName();								if (name.equals("test1")){					try {						connectedSignal.wait();					} catch (InterruptedException e) {						// TODO Auto-generated catch block						e.printStackTrace();					}				}								for (int i = 0; i < 25; ++i) {					sale();				}								if (name.equals("test2")){					connectedSignal.notify();				}				}		}		public synchronized void sale() {			if (connectedSignal.getCount() > 0) {				Thread current = Thread.currentThread();				connectedSignal.countDown();				System.out.println("Thread id" + current.getId() + "value = "http://www.mamicode.com/+ connectedSignal.getCount());"test1");		Thread t2 = new Thread(my, "test2");		t1.start();		t2.start();		connectedSignal.await(); // 等待结束		System.out.println(connectedSignal.getCount());	}}

又花了几分钟稍微改了下， 让两个线程轮流执行


 

import java.util.concurrent.CountDownLatch;public class CountDown {	private static CountDownLatch connectedSignal = new CountDownLatch(50);	static class MyThread implements Runnable {		public void run() {			Thread current = Thread.currentThread();			System.out.println(current.getName());						synchronized (connectedSignal) {				Thread thread = Thread.currentThread();				String name = thread.getName();				//				if (name.equals("test1")){//					try {//						connectedSignal.wait();//					} catch (InterruptedException e) {//						// TODO Auto-generated catch block//						e.printStackTrace();//					}//				}												for (int i = 0; i < 25; ++i) {					if (name.equals("test1") && (i % 2 == 0)){						try {							sale(); 							connectedSignal.notify();							connectedSignal.wait();							connectedSignal.notify();						} catch (InterruptedException e) {							// TODO Auto-generated catch block							e.printStackTrace();						}					}					else{						sale();						connectedSignal.notify();						try {							connectedSignal.wait();							connectedSignal.notify();						} catch (InterruptedException e) {							// TODO Auto-generated catch block							e.printStackTrace();						}					}				}				//				if (name.equals("test2")){//					connectedSignal.notify();//				}				}		}		public synchronized void sale() {			if (connectedSignal.getCount() > 0) {				Thread current = Thread.currentThread();				connectedSignal.countDown();				System.out.println("Thread id" + current.getId() + "value = "http://www.mamicode.com/+ connectedSignal.getCount());"test1");		Thread t2 = new Thread(my, "test2");		t1.start();		t2.start();		connectedSignal.await(); // 等待结束		System.out.println(connectedSignal.getCount());			}}

 

结果和我想的一样。感觉本身线程使用挺简单的，java估计是为了开发者更方便开发， 自己封装再提供了更多的功能，反倒让我很不习惯。

纯粹本人观点， 有错误欢迎指出.

 

Java notify的使用


联系
我们