How to check if a requested file exists in WEB-INF from a Java Servlet?

Question

I'm writing a filter which redirects a .js file to its corresponding .js.gz file, if it exists. So foo.js would go to foo.js.gz. The problem is, how do I check if the corresponding .js.gz file exists in the WEB-INF directory from the servlet?

Currently, if I do

System.out.println(httpServletRequest.getRequestURI());
File f = new File( httpServletRequest.getRequestURI() ); 
System.out.println( f.exists);

I get:

/test.js
false

Even when the file exists.

Answer 1

how do I check if the corresponding .js.gz file exists in the WEB-INF directory from the servlet?

Use ServletContext#getRealPath() method.

File file = new File(request.getServletContext().getRealPath("/WEB-INF/foo.js.gz"));
System.out.println(file.getAbsolutePath());
if(file.exists()){
    System.out.println("file exists");
}

For more info read comments below.