How do i merge multiple .png images as a single image using java?

Question

I want to send multiple .png images as an single image through servlet response.getOutputStream().write(encoder.pngEncode()); But i can send only one image at a time,but i need to send multiple images through response object using java. If anyone knows please give me your inputs.

   // Create a set of charts
   JFreeChart chart1=null;

   BufferedImage buf[] = new BufferedImage[5]; 
   PngEncoder encoder[] = new PngEncoder[5]; 
   for (int i=0; i<5; i++ ) 
   {            
       buf[i] = chart[i].createBufferedImage(400, 350, null); 
       encoder[i] = new PngEncoder( buf[i], false, 0, 9 ); 
       System.out.println("i= "+i); 
       resp.getOutputStream().write( encoder[i].pngEncode() );           
   }

Answer 1

Why do you need to send multiple images through a single response?

While possible by using a multi-part MIME response, this is highly unusual and rarely implemented as the client needs to know how to interpret it. If your client is just some an arbitrary web browser, this approach won't work. If your client is your own applet/software, then maybe.

Another option might be to send a single image that is built up from other images, but that would depend very much on your use case.