GUI：鼠标组件 通过鼠标移动到按钮上更改背景颜色

package cn.idcast2;

import java.awt.Button;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class FrameDemo2 {
	public static void main(String[] args) {
		final Frame f = new Frame();
		f.setBounds(400, 200, 400, 300);
		f.setLayout(new FlowLayout());
		final Button RedButton = new Button("红色");
		final Button GreenButton = new Button("绿色");
		final Button BlueButton = new Button("蓝色");
		final Button RestartButton = new Button("复原");
		f.add(RedButton);
		f.add(GreenButton);
		f.add(BlueButton);
		f.add(RestartButton);
		//设置鼠标，鼠标是个接口，所以需要添加适配器
		RedButton.addMouseListener(new MouseAdapter() {
			@Override
			public void mouseClicked(MouseEvent e) {
				//设置窗体背景
				f.setBackground(Color.RED);
			}
		});
		GreenButton.addMouseListener(new MouseAdapter() {
			@Override
			public void mouseClicked(MouseEvent e) {
				// TODO Auto-generated method stub
				f.setBackground(Color.GREEN);
			}
		});
		BlueButton.addMouseListener(new MouseAdapter() {
			@Override
			public void mouseClicked(MouseEvent e) {
				// TODO Auto-generated method stub
				f.setBackground(Color.BLUE);
			}
		});
		RestartButton.addMouseListener(new MouseAdapter() {
			@Override
			public void mouseClicked(MouseEvent e) {
				// TODO Auto-generated method stub
				f.setBackground(Color.WHITE);
			}
		});
		f.addWindowListener(new WindowAdapter() {
			@Override
			public void windowClosing(WindowEvent e) {
				// TODO Auto-generated method stub
				System.exit(0);
			}
		});
		f.setVisible(true);
	}
}package cn.idcast2;

import java.awt.Button