Retrieve images from a folder outside web root folder using servlet

Question

I\'m trying to create a small servlet that uploads images and is able to retrieve them in a different page as a slideshow.

I\'m able to save them outside the WebApp

Answer 1

You need to understand how HTTP and HTML work:

1. The browser asks for an HTML page (first request)
2. The server sends back HTML (and HTML only), containing 3 tags
3. The browser sends a request to get the bytes of the first image (second request)
4. The server sends back the bytes of the first image
5. The browser sends a request to get the bytes of the second image (third request)
6. The server sends back the bytes of the second image
7. The browser sends a request to get the bytes of the third image (fourth request)
8. The server sends back the bytes of the third image

So, you need a servlet or JSP which generates the HTML page, containing all your tags. Each of this tag should have the following form:

And you need a second servlet, mapped to imageServlet, which reads the bytes of the image identified by the imageId parameter value from the file system, and write those bytes to the response output stream.