Outputting pdf to browser from a db

Question

Hi , I have a web-app that queries a db for a pdf file (Blob) and then outputs the file to the browser. It seems to be downloaded to the browser, but then nothing is displayed. I've used the same code for other apps, which all work fine. I believe it might be server related as it works fine on Tomcat, but not on SunONE. Any ideas? Thanks
             Blob b = rs.getBlob(1);
             int len = 0;
             InputStream is = b.getBinaryStream();
             long length = b.length();
             byte[] x = new byte[10240];
             resp.setHeader("Content-disposition", "filename=temp.pdf");
             resp.setContentType("application/pdf");
             resp.setContentLength( (int) length);
             DataOutputStream o = new DataOutputStream(resp.getOutputStream());
             while ( (len = is.read(x)) != -1)
                o.write(x, 0, len);
             o.flush();
             o.close();
             is.close();

Answer 1

Hi guys,
In my application I am uploading documents of all type and extensions into the orcale database as BLOB objects. When the user clicks a url to view a document I grab the url and then making use of the document ID requested, I query the database and retrieve the corresponding BLOB object as a byte array and then stream the byte array to display the file/image in the browser.
(The application is so designed that all the column values of a row are returned as objects, and then I cast the objects based on the need. In my case I get an object corresponding to my document, which I cast it to byte [] and then stream it.)
I am able to retrieve documents of type MS word and text files. But when I retrieve images I get a blurred/corrupted image. ANd with PDF files I get the following message:
"There was an error processing a page. Too few Operands." and also "Unknown token '' was found".
Even when I open excel sheets and powerpoint files I get an error message.
I am comparing the length of the blob as stored in the db and also length of the blob after retrieving from the db and they are same.
I am using Internet Explorer 6.0 as my browser, Tomcat 4.1 as my app server and Java 1.4.
This is my servlet code.
//retreiving the row from the DB and then casting the Object to byte[]
byte[] bytes = (byte[])dataSetRow.getObjectValue(7);
String contentType = dataSetRow.getValue(2);
response.setContentType(contentType);
String blobStrLen = dataSetRow.getValue(5);
int iLen = Integer.parseInt(blobStrLen);
response.setContentLength(iLen);
ByteArrayOutputStream output = new ByteArrayOutputStream(iLen);
output.write(bytes, 0, iLen);
ServletOutputStream out = response.getOutputStream();
out.write(output.toByteArray(), 0, output.size());
out.flush();
out.close();
Any help will be greatly appreciated , if you need more details please let me know.
Thanks,
anil.