JAva点画不規則に従って図形を閉じる

 public void sketch(List pointList) throws FileNotFoundException , IOException{
        
        BufferedImage bi = new BufferedImage  //       
                (512,512,BufferedImage.TYPE_INT_RGB);//INT       ,RGB   ,  512，  512
        
        Graphics2D g2 = (Graphics2D) bi.getGraphics();//        (      )
        g2.setColor(Color.BLACK);   //      

        g2.fillRect(0, 0, bi.getWidth(), bi.getHeight()); //      
        GeneralPath gp=new GeneralPath(); //shape   ，      

        Point p1=pointList.remove(0);
        Point p2=pointList.remove(0);
        gp.append(new Line2D.Double(p1.x,p1.y,p2.x,p2.y),true); //         
        
        for(Point point: pointList){    //           
            gp.lineTo(point.x,point.y); 
        }
        gp.closePath(); //    
        g2.setColor(Color.WHITE);   //      
        g2.fill(gp);    //    
        ImageIO.write(bi,"JPEG",new FileOutputStream("G:\\a.jpg"));//     JPEG      
    }