Viewing HTML page saved on the server from the browser

Question

Hi all
In my application i am having some HTML pages saved on the server. I had given an option to the user to view the HTML page from my application. behind the scene what i am doing is that the view request will get handled by a servlet and from that servlet iam locating the HTML page on the server directory and sending the HTML page to browser by using the Servlet OutputStream. The HTML page is shown on the browser but the attached images are not shown. The images are also there in the server directory and are refered in the HTML file correctly. When i directly open the HTML file then the images are shown correctly.
Can anyone suggest wat's wrong there.
The code i m using is
ServletOutputStream out=response.getOutputStream();
                    if(format.equalsIgnoreCase("pdf"))
                         logger.info("Seleted format is pdf..\n");
                         response.setContentType("application/pdf");
                    else
                         logger.info("Seleted format is html..\n");
                         response.setContentType("text/html");
String file = ReportingConstants.URL_GENERATEDREPORTS+reportPath+itemName;
// file : HTML file absolute path as string.
                    URL url=new URL(file);                    
                    BufferedInputStream bis=new BufferedInputStream(url.openStream());
                    BufferedOutputStream bos=new BufferedOutputStream(out);
                    byte[] buff = new byte[2048];
                    int bytesRead;
                    while(-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
                         bos.write(buff, 0, bytesRead);
                         bos.flush();
                    }

Answer 1

You have to undertsand how the browser handles images and other resources in a HTML page. In the HTML there is an image tag that has a url to an image which can be a reletive url or an absolute url (starts with a "/").
If the url is a relative url the browser interprets the url as being relative to the url currently displayed in the address field discarding the last element of the url . So if the url in the address bar is http://www.myserver.com/myapp/mypage.html and the relative url is images/myimage.jpg, the browser will submit a request to the server for http://www.myserver.com/myapp/images/myimage.jpg
Now let's say that you are call mypage.html from a servlet that has the url http://www.myserver.com/myapp/servlets/myservlet. Then when the browser tries to retrieve myimage.jpg it will use the url http://www.myserver.com/myapp/servlets/myservlet/images/myimage.jpg and since this is incorrect it will not be able to display the images.
One solution to this is to change all of the image urls to absolute urls. That is the start with a slash where the slash represents the start of the url after the application domain name. For example you used an absolute url for myimage.jpg it would look like /images.myimage.jpg and when accessing the page through the servlet url (http://www.myserver.com/myapp/servlets/myservlet) the browser will discard everything after http://www.myserver.com/myapp and look for the image at http://www.myserver.com/myapp/images/myimage.jpg which is the correct url.
A second solution is to use the HTML BASE tag which tells the browser not to interpret the image tag urls (and other resourses) using the current url in the address bar but to use the url supplied in the HTML BASE tag. The browser will still perform the same process for relative urls but now relative to the BASE tag url. Since the BASE tag url will be the same every time the page is accesssed the images should be correctly accessed no matter how the page is accessed (eg directly, using RequestDistpatcher or via your servlet)