Spring MVC - Generate JSON Example

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The following example shows how to generate JSON using the Spring Web MVC Framework. To start with, let us have a working Eclipse IDE in place and consider the following steps to develop a Dynamic Form based Web Application using the Spring Web Framework −

Step	Description
1	Create a project with a name TestWeb under a package com.tutorialspoint as explained in the Spring MVC - Hello World chapter.
2	Create a Java classes User, UserController under the com.tutorialspoint package.
3	Download Jackson libraries Jackson Core, Jackson Databind and Jackson Annotations from maven repository page. Put them in your CLASSPATH.
4	The final step is to create the content of all the source and configuration files and export the application as explained below.

User.java

package com.tutorialspoint;

public class User {
   private String name;
   private int id;
   public String getName() {
      return name;
   }  
   public void setName(String name) {
      this.name = name;
   }
   public int getId() {
      return id;
   }   
   public void setId(int id) {
      this.id = id;
   }	
}

UserController.java

package com.tutorialspoint;

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("/user")
public class UserController {
	
   @RequestMapping(value="{name}", method = RequestMethod.GET)
   public @ResponseBody User getUser(@PathVariable String name) {

      User user = new User();

      user.setName(name);
      user.setId(1);
      return user;
   }
}

TestWeb-servlet.xml

<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"
   xmlns:mvc = http://www.springframework.org/schema/mvc"
   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 = com.tutorialspoint" />
   <mvc:annotation-driven />
</beans>

Here, we have created a Simple POJO User and in UserController we have returned the User. Spring automatically handles the JSON conversion based on RequestMapping and Jackson jar present in the classpath.

Once you are done with creating source and configuration files, export your application. Right click on your application, use Export → WAR File option and save your TestWeb.war file in Tomcat's webapps folder.

Now, start the Tomcat server and make sure you are able to access other webpages from the webapps folder using a standard browser. Try a URL – http://localhost:8080/TestWeb/mahesh and we will see the following screen.