import javax.swing.*;

import java.awt.*;

public class TestSingleton

{

    public static void main(String args[])

    {

        System.out.println(“System Print Out”);

       int x1=40;

       int y1=40;

       int x2=100;

       int y2=100;

       Color paint_color = Color.blue;

       Video2.getInstance(x1,y1,x2,y2,paint_color);

       for(int i=0;i<3;i++)

       {

           paint_color = Color.red;

           Video2.getInstance(x1+40,y1+40,x2,y2,paint_color);

       }

       System.out.println(“System Print Out”);

    }

}

class Video2 extends JFrame

{

    static int x1;

    static int y1;

    static int x2;

    static int y2;

    static Color paint_color;

    //定义Construct函数，将需要的参数带入

    public Video2(int x1,int y1,int x2,int y2, Color paint_color)

    {

       Video2.x1=x1;

       Video2.y1=y1;

       Video2.x2=x2;

       Video2.y2=y2;

       Video2.paint_color = paint_color;

       setBounds(200,100,200,500);

       setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

       setVisible(true);

    }

    int j=0;

    //@Override

    public void paint(Graphics g)

    {

       System.out.println(++j);

       g.setColor(paint_color);

       g.drawLine(x1, y1, x2, y2);

    }

    public static synchronized Video2 getInstance(int x1,int y1,int x2,int y2,Color paint_color){

        if (instance == null) {

          instance = new Video2(x1, y1, x2, y2, paint_color);

        }

        instance.repaint();

        return instance;

      }

    private static Video2 instance;

}