Java Object notifyAll() 方法

Java String类Java Object 类


Object notifyAll() 方法用于唤醒在该对象上等待的所有线程。

notifyAll() 方法跟 notify() 方法一样,区别在于 notifyAll() 方法唤醒在此对象监视器上等待的所有线程,notify() 方法是一个线程。

如果当前线程不是对象监视器的所有者,那么调用 notifyAll() 方法同样会发生 IllegalMonitorStateException 异常。

语法

public final void notifyAll()

参数

返回值

没有返回值。

实例

以下实例演示了 notifyAll() 方法的使用:

实例

import java.util.Collections; import java.util.LinkedList; import java.util.List; public class RunoobTest { private List synchedList; public RunoobTest() { // 创建一个同步列表 synchedList = Collections.synchronizedList(new LinkedList()); } // 删除列表中的元素 public String removeElement() throws InterruptedException { synchronized (synchedList) { // 列表为空就等待 while (synchedList.isEmpty()) { System.out.println("List is empty..."); synchedList.wait(); System.out.println("Waiting..."); } String element = (String) synchedList.remove(0); return element; } } // 添加元素到列表 public void addElement(String element) { System.out.println("Opening..."); synchronized (synchedList) { // 添加一个元素,并通知元素已存在 synchedList.add(element); System.out.println("New Element:'" + element + "'"); synchedList.notifyAll(); System.out.println("notifyAll called!"); } System.out.println("Closing..."); } public static void main(String[] args) { final RunoobTest demo = new RunoobTest(); Runnable runA = new Runnable() { public void run() { try { String item = demo.removeElement(); System.out.println("" + item); } catch (InterruptedException ix) { System.out.println("Interrupted Exception!"); } catch (Exception x) { System.out.println("Exception thrown."); } } }; Runnable runB = new Runnable() { // 执行添加元素操作,并开始循环 public void run() { demo.addElement("Hello!"); } }; try { Thread threadA1 = new Thread(runA, "Google"); threadA1.start(); Thread.sleep(500); Thread threadA2 = new Thread(runA, "Runoob"); threadA2.start(); Thread.sleep(500); Thread threadB = new Thread(runB, "Taobao"); threadB.start(); Thread.sleep(1000); threadA1.interrupt(); threadA2.interrupt(); } catch (InterruptedException x) { } } }

以上程序执行结果为:

List is empty...
List is empty...
Opening...
New Element:'Hello!'
notifyAll called!
Closing...
Waiting...
Waiting...
List is empty...
Hello!
Interrupted Exception!

Java String类Java Object 类