RequestDispatcher interface

RequestDispatcher is a interface of Servlet API. Implementation of which provided by vendors. This interface provides methods for including contents of a resource (Such as Servlet/html page etc.) to the response of current Servlet or forward the request to another web resource(Such as Servlet/html page etc.).

Methods:

1- getRequestDispatcher():
                                              Method of ServletRequest interface is used to obtain a RequestDispatcher object.
public RequestDispatcher getRequestDispatcher(String URL of Resource);

RequestDispatcher interface provides include() and forward() method for including contents of a resource and to forward the request to another response respectively.

I) include():
                  Is used to include the content of the resource to the response of the current Servlet.

public void include(ServletRequest, ServletResponse) throws ServletException, IOException;

II) forward():
                      Is used to forward request to another resource.

public void forward(ServletRequest, ServletResponse) throws ServletException, IOException;

Note: Real life example (Cases for request handling): Assume counselor is acts as a Servlet Case1: Self give result if any one ask about course CourseName/fee/CourseDuration. Case2: For Some technical Enquiry (such as version of hibernate) ask the Technical Trainer ( Take a Help of another person on same enquiry)  and then give the information (result). Case3: Forward the call direct to the Trainer (Now information (result) is produce by Trainer) .