To use the ?jsp_precompile you simple append it to the URL of the JSP that you wish to compile. For example, if your JSP is located at www.example.com/index.jsp you would enter in the browser's address bar the following: www.example.com/index.jsp?jsp_precompile. It does not take a parameter although you can give it the value true, like so: ?jsp_precompile=true. The JSP will not be executed, but rather compiled.
Alex Theedom - Senior Java EE Developer (OCPJP/OCPJWCD)