need help to generate png image from svg file

[lily zou]

Hi, there
It would be much appreciated if any one could help me out.
I have a servlet where I use PNGTranscoder to generate png image and display it. This is my code:
PNGTranscoder trans = new PNGTranscoder();
File svgFile = new File(SVGFILE);
long svgSize = svgFile.length();
TranscoderInput input = new TranscoderInput(svgURI);
ByteArrayOutputStream outStream
= new ByteArrayOutputStream((int)svgSize);
TranscoderOutput output
= new TranscoderOutput(outStream);
trans.transcode(input,output);

HOWEVER, the page above codes rendered is blank. May I ask why the png file is not created corrected ?
Tons of thanks,
Lily

[Eric Pascarello]

not 100% sure, but it might be this part of the line with the int in ()
ByteArrayOutputStream((int)svgSize);
Eric

[lily zou]

That syntax is correct. I think the reason might be that I used ByteArrayOutputStream as PNGTranscoder's output stream and ByteArrayOutputStream will not out put its contents to browser.
However, PNGTranscoder can only accept ByteArrayOutputStream as it output stream. I am wondering if there is any way that I can get around this problem.

[Andy Bowes]

In order to pass back the contents of the ByteArrayOutputStream as part of the HttpResponse you will need to do something like this at the end of your code:
response.setContentType("image/png");
ServletOutputStream servletOutput =
response.getOutputStream();
servletOutput.write(outStream.toByteArray());
servletOutput.flush();
response.setStatus(HTTPServletResponse.SC_OK);

Hope this is what you are after.
[ April 10, 2003: Message edited by: Andy Bowes ]

[lily zou]

Thanks a lot, Andy. Yes, this is what I need. I need to set contenttype to be image/png.
Thanks again,
Lily