WebObjects/Web Applications/Development/PDF Generation

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Overview[edit]

You might want to also review the Returning a File example.

Zak Burke's Example[edit]

It is important to add "-Djava.awt.headless=true" to the "Additional Arguments" list to suppress a console window running WOBootstrap that will try to pop up and then fail to close, which seems to prevent the thread from returning, which causes the app to hang.

 private ByteArrayOutputStream pdf()
 {
   // binary container for PDF
   ByteArrayOutputStream out = null;
   
   try
   {
     // assume these exist
     String xsl, xml;
     
     TransformerFactory transformerFactory = TransformerFactory.newInstance();
     
     // configure FOP, apache's XML->PDF transformer
     Fop fop = new Fop(MimeConstants.MIME_PDF);
     out = new ByteArrayOutputStream();
     fop.setOutputStream(out);
     
     // configure XSLT transformer
     Source xsltSrc = new StreamSource(new StringReader(xsl));
     Transformer transformer = transformerFactory.newTransformer(xsltSrc);
     
     // pipe XSL transformation through to FOP
     Result res = new SAXResult(fop.getDefaultHandler());
     
     // grab XML input stream
     Source src = new StreamSource(new StringReader(xml));
 
     // Start the transformation and rendering process
     transformer.transform(src, res);
   }
   catch (Exception e)
   {
     // actually, catch the following, one by one:
     // TransformerConfigurationException
     // FOPException
     // TransformerFactoryConfigurationError
     // TransformerException
   }
   
   return out;
 }
 
 public void appendToResponse(WOResponse response, WOContext context)
 {
   ByteArrayOutputStream out = pdf();
   
   // without data, show the PDF page, which is just an error message.
   if (out == null)
     super.appendToResponse(response, context);
   
   // assume this exists
   String filename;
   
   response.setHeader("application/pdf", "Content-Type");
   response.setHeader("" + out.size() + "", "Content-Length");
   response.setHeader("attachment;filename=" + filename, "Content-Disposition");
   response.setContent(new NSData(out.toByteArray()));
 }

Related Links[edit]