用java编写一个计数器或计时器

import java.awt.BorderLayout

import java.awt.Container

import java.awt.Font

import java.awt.GridLayout

import java.awt.event.ActionEvent

import java.awt.event.ActionListener

import javax.swing.JButton

import javax.swing.JFrame

import javax.swing.JOptionPane

import javax.swing.JPanel

import javax.swing.JTextField

public class TimerDemo extends JFrame implements ActionListener {

    private static final long serialVersionUID = 201306211111L

    private JTextField screen = new JTextField("0")

    private JButton start = new JButton("开始")

    private JButton reset = new JButton("重置")

    private JPanel panel = new JPanel()

    private boolean isRunning

    private int time

    private int timeBetween

    public TimerDemo(int timeBetween) {

        super("计时器")

        this.timeBetween = timeBetween

        try {

            init()

        } catch (Exception e) {

            e.printStackTrace()

        }

    }

    public TimerDemo() {

        super("计时器")

        this.timeBetween = 100

        try {

            init()

        } catch (Exception e) {

            e.printStackTrace()

        }

    }

    private void init() {

        panel.setLayout(new GridLayout())

        panel.add(start)

        panel.add(reset)

        start.addActionListener(this)

        reset.addActionListener(this)

        screen.setFont(new Font("幼圆", Font.BOLD, 60))

        screen.setHorizontalAlignment(JTextField.CENTER)

        screen.setEditable(false)

        Container c = getContentPane()

        c.setLayout(new BorderLayout())

        c.add(panel, BorderLayout.SOUTH)

        c.add(screen, BorderLayout.CENTER)

        this.setSize(200, 150)

        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)

        this.setResizable(false)

        this.setLocationRelativeTo(null)

        this.setVisible(true)

    }

    public static void main(String[] args) {

        new TimerDemo(1)// 设定 1ms/次

        // new TimerDemo()

    }

    @Override

    public void actionPerformed(ActionEvent e) {

        if (e.getSource() == start) {

            if (start.getText().equals("开始")) {

                start.setText("暂停")

                isRunning = true

            } else if (start.getText().equals("暂停")) {

                start.setText("开始")

                isRunning = false

            }

        }

        if (e.getSource() == reset) {

            start.setText("开始")

            screen.setText("0")

            isRunning = false

            time = 0

        }

        new Thread(new TimeZone()).start()

    }

    class TimeZone implements Runnable {

        @Override

        public void run() {

            while (isRunning) {

                time++

                if (time >= Integer.MAX_VALUE) {

                    screen.setText("ERROR")

                    JOptionPane.showMessageDialog(null, "ERROR")

                    isRunning = false

                }

                screen.setText(String.valueOf(time))

                try {

                    Thread.sleep(timeBetween)

                } catch (Exception e) {

                    e.printStackTrace()

                }

            }

        }

    }

}

class Computer{

    int value

    Computer(int value){

        this.value=value

    }

    public void add(){

        System.out.println("Value:"+value+"->"+(value+1))

        value++

    }

    public void sub(){

        System.out.println("Value:"+value+"->"+(value-2))

        value-=2

    }

    public void clear(){

        System.out.println("Value:"+value+"->"+0)

        value=0

    }

}

public class Demo{

    public static void main(String[] args){

        Computer computer=new Computer(10)

        computer.add()

        computer.sub()

        computer.clear()

    }

}

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