无法停止Java线程

Question

我正在尝试为特定任务创建一个线程以在另一个类中运行.线程正在启​​动任务,但是当我尝试停止线程时,它没有停止.线程一直持续到循环.你能帮帮我吗？

线程类:

package com.development;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class ThreadExample extends JFrame {
    MyThread mt;
    Thread th;
    ThreadExample(){        
        JPanel p1 = new JPanel();
        p1.setPreferredSize(new Dimension(400,400));
        JButton b1 = new JButton("Start");
        JButton b2 = new JButton("Stop");
        b1.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent arg0) {
                  mt = new MyThread();
                  th = new Thread(mt);
                 th.start();
            }
        });
        b2.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                th.interrupt();               
            }
        });
        p1.add(b1);
        p1.add(b2);
        this.getContentPane().add(p1);
        this.pack();
        this.setVisible(true);
    }
    public static void main(String arg[]) {
        ThreadExample mt = new ThreadExample();
        mt.setVisible(true);
    }
    public class MyThread implements Runnable{
        private volatile boolean runnable=true;
        DisplayMsg dm = new DisplayMsg("Cycle");
        @Override
        public void run() {
            while(!Thread.currentThread().isInterrupted()) {
            // TODO Auto-generated method stub
               dm.show();                 
            }    
        }
    }    
}


DisplayMsg class:

package com.development;

public class DisplayMsg {
    private String dispMsg; 
    private boolean runnable;
    DisplayMsg(String dispMsg){
        this.dispMsg=dispMsg;
    }
    public void show() {
        for(int t=0;t<100;t++) {        
        try {
            System.out.println(dispMsg + t);
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        }
    }   
}

Answer 1

您的DisplayMsg类循环100秒,并忽略中断.实际上,当Thread.sleep()被中断时,它会重置中断状态,然后抛出InterruptedException.由于您忽略了InterruptedException,因此线程会继续,就好像什么也没发生一样.

public void show() {
    for(int t=0;t<100;t++) {        
        try {
            System.out.println(dispMsg + t);
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

不要忽略中断:

public void show() {
    for(int t=0;t<100;t++) {        
        try {
            System.out.println(dispMsg + t);
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            // re-interrupt the thread and stop looping
            Thread.currentThread().interrupt();
            return;
        }
    }
}