在Java编程中,如何显示线程状态?
以下示例演示如何使用Thread
类的isAlive()
和getStatus()
方法显示线程的不同状态。
package com.yiibai;
class MyThreads extends Thread {
boolean waiting = true;
boolean ready = false;
MyThreads() {
}
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 DisplayThreadStatus {
public static void main(String args[]) throws Exception {
MyThreads thrd = new MyThreads();
thrd.setName("MyThreads #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());
}
}
上述代码示例将产生以下结果 -
MyThreads #1 Alive:false State:NEW
MyThreads #1 starting.
waiting:true
waiting:true
alive
....... 省略 ....
alive
MyThreads #1 terminating.
alive
MyThreads #1 Alive:false State:TERMINATED