threadstatus.java

java2应用开发指南第一版

【代码9-2-3】
//ThreadStatus.java
class ThreadStatus
{
public static void main(String args[])
{
        for (int i=0; i<5; i++) 
{
	//创建新的线程对象
Worker worker = new Worker();
//设置线程的优先级
            worker.setPriority(Thread.currentThread().getPriority()-1);
try 
{
	//线程启动
                worker.start();
				//线程睡眠5秒
                Thread.sleep(5000);    // Wait 5 seconds.

                System.out.println("Stopping thread: " + worker);
				//结束线程运行
                worker.safeStop();     // Stop the thread.
}
catch (InterruptedException e)
{
                e.printStackTraceTrace();
            }
        }
    }
}
//线程对象的创建
class Worker extends Thread
{
    private int count;
    private boolean done = false;

	//同步方法，拥有线程的运行终止
synchronized void safeStop()
{
        done = true;
    }
	//判断线程状态
synchronized boolean ok()
{
        return (!done);
}
//线程需要完成的工作
void doWork()
{
        // do something useful here
        ++count;
    }
    //线程的run方法
public void run()
{
        while (ok())
{
            doWork();
        }
    }
}