In This article, you can learn how to Create Business and DB Service Method Implementation using Spring MVC @Service annotation
Refer
Spring MVC Hello World for base project setup.
1. Create a new Interface Service UserService.java and the Class Implementation UserServiceImpl.java
Create a package com.tutorial.service and interface UserService.java
package com.tutorial.service;
import com.tutorial.domain.User;
public interface UserService {
public User getUser();
}
inteface file - This file has only method implementation
Create a package com.tutorial.service and class UserServiceImpl.java
package com.tutorial.serviceImpl;
import com.tutorial.domain.User;
import com.tutorial.service.UserService;
import org.springframework.stereotype.Service;
@Service
public class UserServiceImpl implements UserService {
@Override
public User getUser() {
User user = new User();
user.setAgeGroup("24");
user.setGender("F");
user.setUserName("Usha");
return user;
}
}
implements UserService - This implements the UserService Interface
@Service - This create a instance for the UserService class. The same instance can be used in any other class using @Autowired (Dependency Injection)
2. Bind the UserService instance to the Controller class
Create a package com.tutorail.web and the userController.java file
package com.tutorial.web;
import com.tutorial.domain.User;
import com.tutorial.service.UserService;
import javax.servlet.http.HttpServletRequest;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
@Controller
public class UserController {
@Autowired
public UserService userService;
@RequestMapping("/getUser")
public String getUser(ModelMap map, HttpServletRequest request) {
map.addAttribute("user", userService.getUser());
return "userdetail";
}
}
@Contoller - to declare as controller file
@Autowired - to bind the instance to the UserService class
3. User component-scan in the dispatcher-servlet.xml to scan all the annotated class
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<mvc:annotation-driven />
<context:component-scan base-package="com.tutorial" />
<bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/WEB-INF/pages/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
</beans>
<context:component-scan base-package="com.tutorial"/> - will scan all the classes with the annotation and create a single instance for this
4. Create userDetail.jsp to get the response content that controller method return
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<h3>Access using ModalMap attribute</h3>
Name: ${user.userName}<br/>
Gender: ${user.gender}<br/>
Age Group : ${user.ageGroup}<br/>
</body>
</html>
Output:
Hit the Url
http://localhost:8084/SpringMVC/getUser
Response:
Access using ModalMap attribute
Name: Usha
Gender: F
Age Group : 24
Download the project
https://drive.google.com/file/d/0B_9jt9kIlxciUU1Ib296S212QWc/view?usp=sharing
Awaiting for Administrator approval