Spring MVC Restful Service

Spring MVC Restful Service
 
Hi friends .Today i am going to demonstrate you how spring negotiates with various kinds of content  such as xml,json.however there are two ways through which spring handles content.one is using @ResponseBody and another is using predefined view resolvers. i am going to demonstrate you how internal conversion is hanlded by @ResponseBody.i am showing example of how @ResponseBody converts incoming xml data into xml form.

Here is sample code:

Student.java

package org.demo.model;
import java.util.List;

import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlElementWrapper;
import javax.xml.bind.annotation.XmlRootElement;


@XmlRootElement(name="student")
public class Student
{
   
   
    private int id;
   
    private String name;
    private List<College> collegeList;
   
    public List<College> getCollegeList()
    {
        return collegeList;
    }
   
    @XmlElementWrapper(name="CollegeList")
   
    public void setCollegeList(List<College> collegeList)
    {
        this.collegeList = collegeList;
    }
    public Student() {}
    public Student(int id,String name)
    { this.id=id; this.name=name; }    
    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

   
}
 College.java

package org.demo.model;

import javax.xml.bind.annotation.XmlRootElement;


@XmlRootElement(name="org.demo.model.Student")
public class College
{
    private int id;
    private String collegename;

    public College() {}
   

   
    public College(int id,String collegename) {super();this.id=id; this.collegename=collegename;}
    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getCollegename() {
        return collegename;
    }

    public void setCollegename(String collegename) {
        this.collegename = collegename;
    }

   
}
XmlController.java

package org.demo.controller;

import java.util.ArrayList;
import java.util.List;

import org.demo.model.College;
import org.demo.model.Employee;
import org.demo.model.Student;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
@RequestMapping("/Student")
public class XmlController
{
//invoke in such a manner : http://localhost:8080/SpringXmlJson/Student/1/nisarg
    @RequestMapping(value="{id}/{name}", method = RequestMethod.GET,produces="application/xml")
    public @ResponseBody Student getStudentInXML(@PathVariable int id,@PathVariable String name)
    {

        Student student1 = new Student(id, name);
        College college1= new College(1,"semcom");
        College college2=new College(2,"NVPAS");
      

        List<College> l1 =new ArrayList<>();
        l1.add(college1);
        l1.add(college2);
        student1.setCollegeList(l1);
      
        return student1;
    }
  
 /*   @RequestMapping(value="/Json/{id}/{name}/{age}", method = RequestMethod.GET,produces="application/json")
    public @ResponseBody Employee getStudentInJson(@PathVariable int id,@PathVariable String name,@PathVariable String age)
    {

        Employee employee1= new Employee(id,name,age);
      
        return employee1;
    }*/
   
}

web.xml
<?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" 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>SpringXmlJson</display-name>

 <welcome-file-list>
  <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
 
  <servlet>
      <servlet-name>xmltest</servlet-name>
      <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
  </servlet>
 
  <servlet-mapping>
      <servlet-name>xmltest</servlet-name>
      <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>


Context File(xmltest-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:mvc="http://www.springframework.org/schema/mvc"
    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
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">

    <context:component-scan base-package="org.demo.controller" />

    <mvc:annotation-driven/>

    </beans>

the output will look like as given below:

however i found one bug here.i can't able to get json data if jackson & jaxb jars are already there in classpath.it still gives me same output in xml format.
Hope you will get  my point for any query ping me on pathak.nisarg@yahoo.com
thanks for reading this article.
regards