Question

我正在创建一个简单的计时器，我有一些关于线程的基本知识。我可以通过等待停止当前正在晒黑的线程，但无法通知它显示“illegalmonitorstateexception”。

'import java.awt.*;
 import java.awt.event.*; 
 import java.applet.Applet;
 /* <applet code = "TimerClass" width = 800 height = 600></applet>*/
 public class TimerClass extends Applet implements Runnable, ActionListener
 {
Thread t1;
int i;
TextField sec;
Button start;
Button stop;
boolean isStop;
boolean isAlive;
public void init()
{
    sec = new TextField(10);
    start = new Button("Start");
    stop = new Button("Stop");
    add(sec);
    add(start);
    add(stop);
    start.addActionListener(this);
    stop.addActionListener(this);
    isStop = true;
    t1 = new Thread(this);
}
public void startThread()
{
    t1.start();
    isAlive = true;
}
public void awake()
{
    try
    {
        System.out.println(Thread.currentThread().isAlive());
        synchronized(t1)
        {
            Thread.currentThread().notify();
        }
    }
    catch(Exception e)
    {
        System.out.println(e.toString());
    }
    //Thread.interrupted();
}
synchronized public void run()
{
    do
    {
        try
        {
            Thread.sleep(1000);
            i += 1;
            sec.setText(Integer.toString(i));
            System.out.println(i);
            if(isStop)
            {
                break;
            }
        }
        catch(InterruptedException  ie)
        {
            continue;
        }
    }while(isStop != true); 
}
public void stopThread()
{
    try
    {
        synchronized(t1)
        {
            Thread.currentThread().wait();
        }
    }
    catch(Exception ie)
    {

    }
}
public void paint(Graphics g)
{

}
public void actionPerformed(ActionEvent ae)
{
    if(ae.getActionCommand() == "Start")
    {
        if(!isAlive)
        {
            isStop = false;
            System.out.println("Thread start");
            startThread();
        }
        else
        {
            isStop = false;
            System.out.println("Thread start again" + isStop);
            awake();
        }
    }
    if(ae.getActionCommand() == "Stop")
    {
        isStop = true;
        stopThread();
    }
}
}

需要帮助。

Answer 1

public class TimerClass {
    Thread t1;
    //fileds, initialisation....

    public void init() {
        //Do Something here...
        t1 = new Thread(this);
        t1.start();
        isAlive = true;
    }

    public void stopThread() throws InterrupterException {
        try {
            //Do Something here...
            synchronized(t1) {
                t1.wait();
            }
        }catch(InterrupterException e) { e.printStackTrace(); }
    }

    public void startThread() throws InterrupterException {
        try {
            //Do Something here...
            synchronized(t1) {
                t1.notify()
            }
        }catch(InterrupterException e) { e.printStackTrace(); }
    }
}

如果我没有忘记，那应该是这样的

线程等待睡眠并通知

1 个答案: