mvc-overview.notes
Spring Web MVC Overview
An HTTP client, typically a browser, makes a request to the web server.
A controller, which is an annotated POJO class, receives the request, performs some business logic, and adds data to the model.
The model is simply an extension of a
java.util.map and is used to store the data that is to be displayed to the user.
The controller also determines which view is to be displayed.
The view can be one of several technologies but is typically a JSP page which accesses the model using JSTL and JSP expression language.
The view is rendered and the results are sent back to the client.
using-lishys-notes.notes
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SimpleController.java
package lishy.start.web;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
@Controller
public class SimpleController {
@RequestMapping("/simple-request.html")
public ModelAndView arbitraryMethod() {
ModelAndView modelAndView = new ModelAndView();
modelAndView.setViewName("show-message");
modelAndView.addObject("message", "This is added to the model with the name 'message'");
return modelAndView;
}
}
show-message.jsp
<html>
<body>
<h1>Simple View</h1>
<p style="color:green">${message}</p>
<p>
<a href="../index.html">back</a>
</p>
</body>
</html>
start-servlet.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:p="http://www.springframework.org/schema/p"
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
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd">
<context:component-scan base-package="lishy.start.web"/>
<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver"
p:prefix="/WEB-INF/jsp/"
p:suffix=".jsp"/>
</beans>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
id="WebApp_ID"
version="2.5">
<display-name>Getting Started</display-name>
<servlet>
<servlet-name>start</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>start</servlet-name>
<url-pattern>/app/*</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
</welcome-file-list>
</web-app>
index.html
<html>
<body>
<h1>Getting Started</h1>
<p>
<a href="app/simple-request.html">Simple Request</a>
</p>
</body>
</html>
We start with a high-level overview of Spring Web MVC.