[eStore] Build simplest spring MVC project with maven

1. Configuration of maven, pom.xml:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.cisco</groupId>
    <artifactId>eStore</artifactId>
    <packaging>war</packaging>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <spring.version>5.0.5.RELEASE</spring.version>
        <servlet.version>3.0.1</servlet.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>${servlet.version}</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>
    </dependencies>

</project>

The core/context/beans is the basic core components of Spring framework. And the servlet is necessary for web project.

2. create the simplest project hierarchy

3. web.xml config

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0">
    <display-name>Archetype Created Web Application</display-name>

    <servlet>
        <servlet-name>spring-mvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>

    <servlet-mapping>
        <servlet-name>spring-mvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    
    <welcome-file-list>
        <welcome-file>/demo/index</welcome-file>
    </welcome-file-list>
</web-app>

4. spring-mvc-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:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation=" http://www.springframework.org/schema/beans  http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context  http://www.springframework.org/schema/context/spring-context-3.0.xsd">
    <context:component-scan base-package="com.cisco.eStore" />
    <context:annotation-config />
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/view/" />
        <property name="suffix" value=".jsp" />
    </bean>
</beans>

5. Controller

package com.cisco.eStore.controller;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
@RequestMapping("/demo")
public class HelloWorldController {

    @RequestMapping("index")
    public String index(Model model){
        model.addAttribute("msg","Hello World!");
        return "demo";
    }

}

6. view/jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>首页</title>
</head>
<body>
<h1>This is SpringMVC Demo</h1>
${msg}
</body>
</html>

Conclusion:

    The dispatchServlet is the main entry for spring mvc framework. Every request will first enter the dispatcherServlet, then using the spring rule to dispatcher to your controller or handler or interceptor .