This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
You can send an image to a browser without writing a file using a servlet. The response type of the servlet would be the image mime type (e.g. image/png for png files) and instead of writing the image data to a file output stream you would send it to the servlet's output stream.
in the servlet it might look something like this...
If you call this servlet as the URL for your image then the browser should display it