第四个参数是在哪上面画就通知谁

package expression;

import java.awt.Canvas;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.image.ImageObserver;
import java.awt.image.ImageProducer;

import javax.swing.ImageIcon;
import javax.swing.JFrame;

import org.omg.CORBA.PUBLIC_MEMBER;

public class Text extends JFrame{
	public  Text(){
		setBounds(200, 200, 500, 500);
		setVisible(true);
		setTitle("绘图");
		setDefaultCloseOperation(EXIT_ON_CLOSE);
		add(new mycanvas());
	}
	public static void main(String[] args) {
		new Text().setVisible(true);
	}
	
	class mycanvas extends Canvas{//内部类
		
	 public void paint(Graphics g){
		 Image image = new ImageIcon("src/ycy.jpg").getImage();//获取图片资源
		 g.drawImage(image, 100, 100, this);//绘制图像
		
	}
 }
}