why
getRequestDispatcher(String path) of the ServletRequest interface cannot extend outside the current servlet context
where as
getRequestDispatcher(String path) of the ServletContext can use the getContext(String uripath) method to obtain RequestDispatcher for resources in foreign contexts.
and how??
Please help
I think you will understand it through these examples below.
Source code structure:
/src/main/webapp/subdir/sample.jsp
/src/main/webapp/sample.jsp
Context is: TestApp
So the entry point: http://yourhostname-and-port/TestApp
Forward to RELATIVE path:
Using servletRequest.getRequestDispatcher("sample.jsp"):
http://yourhostname-and-port/TestApp/subdir/fwdServlet ==> \subdir\sample.jsp
http://yourhostname-and-port/TestApp/fwdServlet ==> /sample.jsp
Using servletContext.getRequestDispatcher("sample.jsp"):
http://yourhostname-and-port/TestApp/subdir/fwdServlet ==> java.lang.IllegalArgumentException: Path sample.jsp does not start with a "/" character
http://yourhostname-and-port/TestApp/fwdServlet ==> java.lang.IllegalArgumentException: Path sample.jsp does not start with a "/" character
Forward to ABSOLUTE path:
Using servletRequest.getRequestDispatcher("/sample.jsp"):
http://yourhostname-and-port/TestApp/subdir/fwdServlet ==> /sample.jsp
http://yourhostname-and-port/TestApp/fwdServlet ==> /sample.jsp
Using servletContext.getRequestDispatcher("/sample.jsp"):
http://yourhostname-and-port/TestApp/subdir/fwdServlet ==> /sample.jsp
http://yourhostname-and-port/TestApp/fwdServlet ==> /sample.jsp