Java Object notifyAll() 方法
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
无 。
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!
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