Problem displaying pdf

[ALi Taimur]

Hello,

I need to display some pdf files which are sitting in a sub-folder inside WEB-INF. The path to the pdf is passed as a parameter from a jsp. The problem I am having is that instead of looking at the context path of my web-app, servlet is trying to load the pdf from the absolute path. For example, if the I pass the path /WEB-INF/HTMLHelp/common/sample.pdf, it goes to my hard drive and tries to look up
c: \WEB-INF\HTMLHelp\common\sample.pdf instead of going to the root of my application. Please let me know what I am doing wrong. Thanks in advance

import java.io.BufferedInputStream;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
 
public class OpstopPDFServlet extends HttpServlet 
{
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException 
    {
     doPost(request,response);
 

    }
 
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//start
    String filename =(String)request.getParameter("url");
   
     
        if(filename == null || filename=="")
        {
       throw new ServletException("Invalid or non-existent pdf"); 
        }
    
        ServletOutputStream stream=null;
        BufferedInputStream buf=null;
        
        try{
    stream=response.getOutputStream();
   
    File pdf= new File(filename);
    exist=true;
    response.setContentType("application/pdf");
      response.addHeader("Content-Disposition","inline;filename="+filename.substring(filename.lastIndexOf('/')+1));
    response.setContentLength((int)pdf.length());
    ClassLoader loader = Thread.currentThread().getContextClassLoader();
    InputStream input =loader.getResourceAsStream(filename);
            
    buf=new BufferedInputStream(input);
    int readBytes=0;
 
    while((readBytes=buf.read())!=-1)
 
    stream.write(readBytes);
   
    }
    catch(IOException ioe)
 
    {
    throw new ServletException(ioe.getMessage());
 

    }
 

    finally{
    if(stream!=null)    
    stream.close();
    if(buf!=null)
    buf.close();
    
    }  
    
 //end   
 
  }
}
    

[Bear Bibeault]

String filename =(String)request.getParameter("url");
...
File pdf= new File(filename);

It's doing exactly what you are telling it to do. What would make you think that the File object would somehow magically detect that you want to make the filename you pass to it relative to another folder?

You need to tell the File object the complete path to the file you want to open.

Hint: check out the ServletContext.getRealPath() method.
[ July 25, 2006: Message edited by: Bear Bibeault ]

[Bear Bibeault]

P.S.

String filename =(String)request.getParameter("url");

Why are you bothering to cast a String to a String?

[Gregg Bolinger]

That's a common mistake I find myself making every now and again. I forget that getParameter returns a String and not an Object.

[Ben Souther]

If you're storing the files under WEB-INF (or anwhere within your webapp's directory structure) you shouldn't be using absolute file paths.
Look at ServletContext.getResourceAsStream.

Depending on how your app is deployed, getRealPath may or may not return a null value.