事件监听

import com.sun.jdi.PathSearchingVirtualMachine;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TestActionEvent02 {
    public static void main(String[] args) {
      //两个按钮，实现一个监听
        //开始 停止
        Frame frame = new Frame("开始-停止");
        Button button1 = new Button("start");
        Button button2 = new Button("stop");

        //可以显示的定义出发会返回的命令，如果不显示定义，则会走默认值
        //可以多个按钮只写一个监听类
        button2.setActionCommand("button2-stop");

        MyMonitor myMonitor = new MyMonitor();

        button1.addActionListener(myMonitor);
        button2.addActionListener(myMonitor);

        frame.add(button1,BorderLayout.NORTH);
        frame.add(button2,BorderLayout.SOUTH);

        frame.setVisible(true);

    }
}

class MyMonitor implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println("按钮被点击了：msg=>"+e.getActionCommand());
        e.getActionCommand();
    }
}

多个按钮，共享一个事件