Spring MVC step by step with maven-Part1

Spring is widely used MVC framework for java developers.Its simple but minimize a lot of ambiguous code by implementing different design pattern. Spring consists of different container. Spring use a concept Dependency Injection which minimizes a lot of ambiguous code.We learn that things later.First we build a Hello world project using Spring.

To build a web project in java firstly we need a Deployment Descriptor(DD) which locate our servlet location.So we can write a DD which places in a xml file named by web.xml. place in /WEB_INF/ directory

**************************************web.xml********************************

<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">

<display-name>Flopcoder Spring MVC step by step</display-name>

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

<servlet-mapping>
<servlet-name>dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
*********************************End***********************************

Now we need a dispatcher servelet where we configure beans.

***************************dispatcher-servlet.xml********************************

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">

    <context:component-scan base-package="com.flopcoder.controller"/>

    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

</beans>
**********************************End*************************************
Above file scan the controller package and for view resolver here we use InternalResourceViewResolver.


Because it is a maven project we need a pom.xml file.

*********************************pom.xml******************************************

<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/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.springapp</groupId>
    <artifactId>HelloWorldSpring</artifactId>
    <packaging>war</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>HelloWorldSpring</name>

    <properties>
        <spring.version>4.0.2.RELEASE</spring.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.1</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>${spring.version}</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.8.2</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <finalName>HelloWorldSpring</finalName>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-surefire-plugin</artifactId>
                <configuration>
                    <includes>
                        <include>**/*Tests.java</include>
                    </includes>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

*************************************End**************************************


I will provide a maven tutorial later.For now i guess everyone know about maven

Now we need a controller class to handle the request

***********************************WelcomeController.java**************************

package com.flopcoder.controller;

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

@Controller
@RequestMapping("/")
public class WelcomeController {
@RequestMapping(method = RequestMethod.GET)
public String sayHello(ModelMap model) {
        model.addAttribute("message", "Hi Viewers Welcome to learn spring Step By Step. This is part 1.");
return "hello";
}
}
*****************************End**********************************************

Controller redirect the request to hello view which is hello.jsp from /WEB-INF/views mapping by InternalViewResolver


**********************************hello.jsp***************************************

<html>
<body>
<h1>${message}</h1>
</body>
</html>

************************************End*****************************************


Here Is a project to introduced for spring framework with maven.I will publish next step more advance about spring.Thanks