Java 实例 - 状态监测
以下实例演示了如何通过继承 Thread 类并使用 currentThread.getName() 方法来监测线程的状态:
Main.java 文件
class MyThread extends Thread{
boolean waiting= true;
boolean ready= false;
MyThread() {
}
public void run() {
String thrdName = Thread.currentThread().getName();
System.out.println(thrdName + " starting.");
while(waiting)
System.out.println("waiting:"+waiting);
System.out.println("waiting...");
startWait();
try {
Thread.sleep(1000);
}
catch(Exception exc) {
System.out.println(thrdName + " interrupted.");
}
System.out.println(thrdName + " terminating.");
}
synchronized void startWait() {
try {
while(!ready) wait();
}
catch(InterruptedException exc) {
System.out.println("wait() interrupted");
}
}
synchronized void notice() {
ready = true;
notify();
}
}
public class Main {
public static void main(String args[])
throws Exception{
MyThread thrd = new MyThread();
thrd.setName("MyThread #1");
showThreadStatus(thrd);
thrd.start();
Thread.sleep(50);
showThreadStatus(thrd);
thrd.waiting = false;
Thread.sleep(50);
showThreadStatus(thrd);
thrd.notice();
Thread.sleep(50);
showThreadStatus(thrd);
while(thrd.isAlive())
System.out.println("alive");
showThreadStatus(thrd);
}
static void showThreadStatus(Thread thrd) {
System.out.println(thrd.getName() + "Alive:=" + thrd.isAlive() + " State:=" + thrd.getState());
}
}
class MyThread extends Thread{
boolean waiting= true;
boolean ready= false;
MyThread() {
}
public void run() {
String thrdName = Thread.currentThread().getName();
System.out.println(thrdName + " starting.");
while(waiting)
System.out.println("waiting:"+waiting);
System.out.println("waiting...");
startWait();
try {
Thread.sleep(1000);
}
catch(Exception exc) {
System.out.println(thrdName + " interrupted.");
}
System.out.println(thrdName + " terminating.");
}
synchronized void startWait() {
try {
while(!ready) wait();
}
catch(InterruptedException exc) {
System.out.println("wait() interrupted");
}
}
synchronized void notice() {
ready = true;
notify();
}
}
public class Main {
public static void main(String args[])
throws Exception{
MyThread thrd = new MyThread();
thrd.setName("MyThread #1");
showThreadStatus(thrd);
thrd.start();
Thread.sleep(50);
showThreadStatus(thrd);
thrd.waiting = false;
Thread.sleep(50);
showThreadStatus(thrd);
thrd.notice();
Thread.sleep(50);
showThreadStatus(thrd);
while(thrd.isAlive())
System.out.println("alive");
showThreadStatus(thrd);
}
static void showThreadStatus(Thread thrd) {
System.out.println(thrd.getName() + "Alive:=" + thrd.isAlive() + " State:=" + thrd.getState());
}
}
以上代码运行输出结果为:
……
alive
alive
MyThread #1 terminating.
alive
……