Problem with opening PDF files from JSF page using SDO

Question

Hi all,
I'm new with JSF and was attempting to read a PDF file from a Database using SDO and JSF. The code below throws an exception when casting from DataObject to Blob. The getLcDoc() method was created by WSAD when I dragged an SDO relational record onto the JSF page. This method returns an DataObject type which I tried casting to a Blob type before using it further. However, an exception is thrown.
Any feedback is appreciated.
Arv
try {
               FacesContext faces = FacesContext.getCurrentInstance();
               HttpServletResponse response =(HttpServletResponse) faces.getExternalContext().getResponse();
               Blob file= (Blob)getLcDoc().get("ATTACH");
               int iLength = (int)(file.length());
               response.setHeader("Content-type", "application/pdf");
               response.setHeader("Content-Disposition", "inline; filename=Attachment");
               response.setHeader("Expires","0");
               response.setHeader("Cache-Control","must-revalidate, post-check=0, pre-check=0");
               response.setHeader("Pragma","public");
               response.setContentLength(iLength);
               ServletOutputStream os = response.getOutputStream();
               InputStream in = null;
               in = file.getBinaryStream();
               byte buff[] = new byte[1024];
               while (true) {
               int i = in.read(buff);
               if (i<0) break;
               os.write(buff,0,i);
               os.flush();
               os.close();
     } catch(Exception ex){
          System.out.println("Error while reading file : " + ex.getMessage());
     }

Answer 1

Hi...I found out that there is actually no need to use a Blob object at all. You can simply call the OutputStreams write() method and pass the DataObject.getBytes() method that returns a byte[] array. The revised code is shown at the end of this posting.
However, a few other teething problems exist:
1. This works well only if I specify the content type in response.setHeader() method. What if my users upload different types of files, is there a way that the browser opens according to the file type without setting the content type?
2. I still have a problem opening PDF files, even if I specify - response.setHeader("Content-type", "application/pdf");
I get the message - The file is damaged and could not be repaired
3. I would also like this to open the attachment in a new window and using target="_blank" doesn't seem to work as seen below:
<h:commandLink
                                             styleClass="commandLink" id="link1" action="#{pc_DocumentDetailsRead.doLink1Action}" target="_blank">
                                             <h:outputText id="text5" styleClass="outputText"
                                                  value="Click Here"></h:outputText>
                                        </h:commandLink>
------------------------Revised code-----------------------------------------
FacesContext faces = FacesContext.getCurrentInstance();
               HttpServletResponse response =(HttpServletResponse) faces.getExternalContext().getResponse();
               response.setHeader("Content-type", "application/msword");
               response.setHeader("Content-Disposition", "inline; filename=Attachment");
               response.setHeader("Expires","0");
               response.setHeader("Cache-Control","must-revalidate, post-check=0, pre-check=0");
               response.setHeader("Pragma","public");
               ServletOutputStream os = response.getOutputStream();
               os.write(getLcDoc().getBytes("ATTACH"));
               os.flush();
               os.close();