Display PDF in browser with a servlet

Question

I want to display a PDF file in browser. I have the path to the pdf in JS and I am making a call to grab the PDF as a servlet from java. Here's what I have so far:

JavaScript:

RequestManager.getJSON(Config.server + "getPDF.json?pdfPath=" + this.pathToPdfFile, (function(data){
        $("#" + this.divId).append('<object id="' + this.pdfObjectId + '" data="' + data + '" type="application/pdf" width="600" height="800"></object>');
        ResizeManager.addResizeHandler(this.pdfObjectId, this.divId, -10, -10);
    }).bind(this));

Java:

@RequestMapping("/getPDF")
public void pdfPathToServlet(Model model, HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
    String pdfPath = request.getParameter("pdfPath");
    if (pdfPath == null || pdfPath.equals(""))
        throw new ServletException("Invalid or non-existent file parameter in UrlServlet servlet.");

    if (pdfPath.indexOf(".pdf") == -1)
        pdfPath += ".pdf";

    File pdf = new File(pdfPath);
    String pdfName = pdfPath.substring(pdfPath.lastIndexOf("/") + 1, pdfPath.length());
    logger.debug(pdfName);
    ServletOutputStream stream = null;
    BufferedInputStream buf = null;
    try 
    {
        stream = response.getOutputStream();
        response.setContentType("application/pdf");
        response.setHeader("Content-Disposition", "inline; filename='" + pdfName + "'");
        FileInputStream input = new FileInputStream(pdf);
        response.setContentLength((int) pdf.length());
        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();
    }
}

My problem is that this is showing the binary output in my browser as text.

I'm not sure what I am doing incorrectly. I have tried changing the header to be attachment instead of inline, but that showed the same thing. I believe I want inline though, as I wish to show it in browser and not download it.

Solution

Your JavaScript part makes no sense. You're obtaining a PDF file as ajax response and then attempting to set it as data attribute of the <object> element. The data attribute must point to a real URL, not to the file content. Fix your JS accordingly:

$("#" + this.divId).append('<object id="' + this.pdfObjectId + '" data="' + Config.server + "getPDF.json?pdfPath=" + this.pathToPdfFile + '" type="application/pdf" width="600" height="800"></object>');

The webbrowser will take care about sending the appropriate HTTP request on the given URL and initializing/rendering the <object> element using the Adobe Acrobat Reader plugin — if any available, I'd rather enclose a <a href="pdfURL">PDF</a> inside the <object> so that there's at least a graceful degradation to a download link.

---

Unrelated to the concrete question, that Java code is not part of a servlet at all, but a Spring MVC action. I recommend to get your terms straight and read in our Servlets wiki page to learn what they really are.

Comments

[Michael-O]

That is not true. If you cann the initial url in the browser with inline header value the PDF plugin will open up in the browser otherwise it will open a new PDF viewer window.

[Diodeus - James MacFarlane]

From an AJAX call? I'm not so sure.

[BalusC]

Even attachment wouldn't have worked at all. JS has for obvious security reasons no facilities to force a Save As dialogue with arbitrary content hold in some variable. The whole answer just doesn't apply. Note that inline works definitely on a synchronous request, provided that the browser has the appropriate plugin for it (Adobe Reader).

[user856354]

Also, I apologize for the poor terminology. I normally don't work on this side of things at all. Recent employment changes have thrown me onto this temporarily and I'm working against a very, very tight deadline. Trying to pick things up when running full speed towards a wall.

[BalusC]

You could however also have used a servlet for the job. That's more than often done, even when already using a MVC framework. Perhaps that's where the confusion is caused.