Hi To All

What is the difference between ServleRequest.getRequestDispatcher() and ServletContext.getRequestDispatcher()

regards
venkadesh

 

 

from javadoc

getRequestDispatcher

public RequestDispatcher getRequestDispatcher(java.lang.String path)Returns a RequestDispatcher object that acts as a wrapper for the resource located at the given path. A RequestDispatcher object can be used to forward a request to the resource or to include the resource in a response. The resource can be dynamic or static.
The pathname specified may be relative, although it cannot extend outside the current servlet context. If the path begins with a "/" it is interpreted as relative to the current context root. This method returns null if the servlet container cannot return a RequestDispatcher.

The difference between this method and ServletContext.getRequestDispatcher(java.lang.String) is that this method can take a relative path.

What this means is that with the ServletContext's RequestDispatcher, the path is always set to the root of the context , ie '/' as compared to the Request's RequestDispatcher where you could specify a path relative to the resource servicing that request.

A simple example

Assume the resource that's servicing the current request is servlet/FirstServlet

Assume, i need to get to a resource /servlet/someOtherServlet using a request disptacher.

   RequestDispatcher rd = getServletContext().getRequestDispatcher("/servlet/someOtherServlet");
   rd.include(request, response);
 
Alternatively
 
    RequestDispatcher rd = request.getRequestDispatcher("someOtherServlet"); //path relative to firstServlet
   rd.include(request, response);

cheers,
ram.

 

 

servletRequest.getRequestDispatcher("\relative Path") takes relative path( means current working directory).

But servletContext.getRequestDispatcher("\absolute Path") takes absolute path( means with root path)

 

 

Congratulations man_bsl on providing a redundant answer to a post almost three years old.

Was there a reason to revive this thread from the depths and say almost exactly the same thing, but slightly wrong?