面板重绘怎么做？

[baidu_38644771]

我做的是在画布上画点、线、面，以ArrayList的形式将坐标存到TXT文件中，现在已经实现了读取TXT文件的内容，遇到的问题是：如何再将读到的坐标点画到画布上？读取的代码如下：
if (pFileChooser.showOpenDialog(canvas1) == JFileChooser.APPROVE_OPTION)
{
try
{
//打开文件
File[] fileFiles = pFileChooser.getSelectedFiles();
for (int j = 0; j < fileFiles.length; j++)
{
System.out.println(fileFiles[j].getName());
if(fileFiles[j].getName().equals("点.txt")){
br=new BufferedReader(new FileReader(fileFiles[j]));
while((r=br.readLine())!=null){
rt=rt+r;
}

StringTokenizer strtr = new StringTokenizer(rt," ");
System.out.println( "Token Total: " + strtr.countTokens() );
while(strtr.hasMoreElements() ){
String lst=strtr.nextToken();
int k=0;
StringTokenizer strts = new StringTokenizer(lst,",");
System.out.println( "Token Total: " + strts.countTokens()/2 );
//int pointx,pointy;
while(strts.hasMoreElements() ){
if(k%2==0){
orgX=Integer.parseInt(strts.nextToken());
System.out.println( orgX );
}
if(k%2==1){
orgY=Integer.parseInt(strts.nextToken());
System.out.println( orgY );
points.add(new Point(orgX,orgY));

}
k=k+1;
System.out.println( strts.nextToken() );
points.add(new points(point));
}

}
}
}