Introducing Spring Framework

Chapter 10 ■ Showing Your Spring Application on the Web
After creating the web application structure (this is the standard structure for a web application) and before you
continue with the code, let’s talk about the MVC design pattern and how the Spring MVC extension helps you to use
this pattern effectively.
Spring MVC
The Spring Framework provides the Spring MVC extension that supports the MVC pattern and features such as i18n,
support for different view engines, theming, and others. Figure 10-1 shows the Spring MVC at a high level.
Incoming
Request
Return
Response
Return
Control
Front Controller
DispatcherServlet
Model
Render
Response
Delegate
Request
Model
Delegate
Rendering of
Response
Handle
Request
Controller
@Controller
Create
Model
View Template
HTML/JSP/JSPX
3rd Party Engines
Figure 10-1. Spring MVC
Figure 10-1 shows how the MVC design pattern works; first there is a request from the user to the front controller
(the Spring’s DispatcherServlet); then it delegates its request to a controller (your own implementation) that will
create a model; then it will delegate the response to the view, in this case the view template (a JSP/JSPX) that will
return the control to the front controller and return the response to the user.
But let’s start coding, so we can see your Spring application on the Web. First, you are going to start creating a
controller that will create the model, and then this controller will delegate the rendering response (with the name of
the view) through the DispatcherServlet. Listing 10-3 shows the delegate.
Listing 10-3. SearchController.java
package com.apress.isf.spring.web;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import com.apress.isf.spring.data.DocumentDAO;
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