getNamedDispatcher() vs. getRequestDispatcher()

getNamedDispatcher(ServletName)

takes the Servlet name as parameter declared in web.xml and returns the RequestDispatcher.

<servlet>

    <servlet-name>FirstServlet</servlet-name>

    <servlet-class>com.genius.ServletExample</servlet-class>

</servlet>

RequestDispatcher dispatch = request.getNamedDispatcher("FirstServlet");

dispatch.forward(request, response);

Note : A servlet instance can determine its name using servletConfig.getServletName();

which returns the name of the class that implements or extend Servlet / HttpServlet.

getRequestDispatcher(URLPattern)

takes URL pattern of servlet and returns the RequestDispatcher.

<servlet-mapping>

    <servlet-name>Test</servlet-name>

    <url-pattern>/tes</url-pattern>

</servlet-mapping>

RequestDispatcher dispatch = request.getRequestDispatcher("/tes");

To forward a request to a JSP page we can use :

RequestDispatcher dispatch = request.getRequestDispatcher("/TestJspOne.jsp");

Here "/TestJspOne.jsp" will look the JSP page at the context root of the application.