package com.yang;

 import java.awt.Color;

 import java.awt.Graphics;

 import java.util.ArrayList;

 import java.util.List;

 import javax.swing.JFrame;

 import javax.swing.JPanel;

 public class drawlineforspline extends JFrame{

     private static final long serialVersionUID = 1L;

     static List <mypoint>plist;

     public static class mypoint{

         int x;

         int y;

         public mypoint(int x,int y){

             this.x=x;

             this.y=y;

         }

     }

     public drawlineforspline(){

         init();

     }

     public drawlineforspline(ArrayList plist){

         init();

         this.plist=plist;

     }

     private void init(){

         this.setTitle("drawline");

         this.setBounds(200, 200, 500, 400);

         this.setBackground(Color.white);

         this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

         this.setLocationRelativeTo(null);

         this.setVisible(true); 

         plist =new ArrayList();

         plist.add(new mypoint(50,80));

         plist.add(new mypoint(50,120));

         plist.add(new mypoint(80,50));

         plist.add(new mypoint(150,10));

         plist.add(new mypoint(180,80));

         plist.add(new mypoint(230,200));

     }

     public class Mypanel extends JPanel{

         public void paint(Graphics g){

             mypoint fromP=new mypoint(50,80);

             mypoint toP=new mypoint(370,240);

             for(int i=0;i<plist.size()-1;i++){

                 g.drawLine(plist.get(i).x, plist.get(i).y, plist.get(i+1).x, plist.get(i+1).y);

             }

         }

     }

     public static void main(String[] args) {

         drawlineforspline d=new drawlineforspline();

         Mypanel myp=d.new Mypanel();

         d.add(myp);

     }

 }