Steps to setup a Spring Web MVC project on eclipse Helios:
1. Create a new Dynamic Web Project name "SpringWebMVC".
2. Create a JSP, 'SpringWebMVC/WebContent/index.jsp' with contents:
<html>
<head><title>Example :: Spring Application</title></head>
<body>
<h1>Example - Spring Application</h1>
<p>This is my test.</p>
</body>
</html>
3. Create 'SpringWebMVC/WebContent/WEB-INF/web.xml', with contents:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" >
<welcome-file-list>
<welcome-file>
index.jsp
</welcome-file>
</welcome-file-list>
</web-app>
4. Run the web app on any server and access it through URL: "http://localhost:8080/SpringWebMVC/"
5. Modify 'web.xml' to add the spring's servlet DispatcherServlet (also known as a 'Front Controller').
It is going to control where all our requests are routed.
<servlet>
<servlet-name>springapp</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springapp</servlet-name>
<url-pattern>*.htm</url-pattern>
</servlet-mapping>
We have decided to let any URL with an '.htm' extension be routed to the 'springapp' servlet (the DispatcherServlet).
6. Create a file called 'springapp-servlet.xml' in the 'SpringWebMVC/WebContent/WEB-INF' directory. This file contains the bean definitions (plain old Java objects) used by the DispatcherServlet. It is the WebApplicationContext where all web-related components go. The name of this file is determined by the value of the <servlet-name/> element from the 'web.xml', with '-servlet' appended to it (hence 'springapp-servlet.xml'). This is the standard naming convention used with Spring's Web MVC framework.
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
<!-- the application context definition for the springapp DispatcherServlet -->
<bean name="/hello.htm" class="springapp.web.HelloController"/>
</beans>
Added a bean entry named '/hello.htm' and specify the class as springapp.web.HelloController. This defines the controller that our application will be using to service a request with the corresponding URL mapping of '/hello.htm'. The Spring Web MVC framework uses an implementation class of the interface called HandlerMapping to define the mapping between a request URL and the object that is going to handle that request (the handler). Unlike the DispatcherServlet, the HelloController is responsible for handling a request for a particular page of the website and is also known as a 'Page Controller' (Fowler). The default HandlerMapping that the DispatcherServlet uses is the BeanNameUrlHandlerMapping; this class will use the bean name to map to the URL in the request so that the DispatcherServlet knows which controller must be invoked for handling different URLs.
7. Copy Spring libraries to the 'WEB-INF/lib' folder:
commons-logging.jar
org.springframework.asm-3.1.1.RELEASE.jar
org.springframework.beans-3.1.1.RELEASE.jar
org.springframework.context-3.1.1.RELEASE.jar
org.springframework.core-3.1.1.RELEASE.jar
org.springframework.expression-3.1.1.RELEASE.jar
org.springframework.web-3.1.1.RELEASE.jar
org.springframework.web.servlet-3.1.1.RELEASE.jar
8. Create the controller, 'src/springapp.web.HelloController'.
public class HelloController implements Controller {
protected final Log logger = LogFactory.getLog(getClass());
public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
logger.info("Returning hello view");
return new ModelAndView("hello.jsp");
}
}
In Spring Web MVC, the Controller handles the request and returns a ModelAndView - in this case, one named 'hello.jsp'/
The model that this class returns is actually resolved via a ViewResolver. Since we have not explicitly defined a ViewResolver, we are going to be given a default one by Spring that simply forwards to a URL matching the name of the view specified.
Reading:
About using a view resolver and annotation based configuration.
http://blogs.sourceallies.com/2010/02/taking-advantage-of-spring-mvcs-default-behavior/
