Spring MVC - Generate JSON Example

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 Spring Web Framework −

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.tutorialspoint</groupId>
   <artifactId>hello</artifactId>
   <version>0.0.1-SNAPSHOT</version>
   <packaging>war</packaging>
   <name>hello Maven Webapp</name>
   <url>http://www.tutorialspoint.com</url>
   <properties>
      <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
      <maven.compiler.source>24</maven.compiler.source>
      <maven.compiler.target>24</maven.compiler.target>
      <org.springframework.version>7.0.0-M9</org.springframework.version>
   </properties>
   <dependencies>
      <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
         <version>4.13.1</version>
         <scope>test</scope>
      </dependency>
      <dependency>
         <groupId>jakarta.servlet</groupId>
         <artifactId>jakarta.servlet-api</artifactId>
         <version>6.0.0</version>
         <scope>provided</scope>
      </dependency>
      <dependency>
         <groupId>org.springframework</groupId>
         <artifactId>spring-context</artifactId>
         <version>${org.springframework.version}</version>
         <scope>compile</scope>
      </dependency>
      <dependency>
         <groupId>org.springframework</groupId>
         <artifactId>spring-webmvc</artifactId>
         <version>${org.springframework.version}</version>
         <scope>compile</scope>
      </dependency>
      <dependency>
         <groupId>com.rometools</groupId>
         <artifactId>rome</artifactId>
         <version>2.1.0</version>
      </dependency>
      <dependency>
         <groupId>tools.jackson.core</groupId>
         <artifactId>jackson-core</artifactId>
         <version>3.0.0</version>
      </dependency>
      <dependency>
         <groupId>tools.jackson.core</groupId>
         <artifactId>jackson-databind</artifactId>
         <version>3.0.0</version>
      </dependency>
      <dependency>
         <groupId>com.fasterxml.jackson.core</groupId>
         <artifactId>jackson-annotations</artifactId>
         <version>3.0-rc5</version>
      </dependency>
   </dependencies>
   <build>
      <finalName>hello</finalName>
      <pluginManagement>
         <plugins>
            <plugin>
               <artifactId>maven-clean-plugin</artifactId>
               <version>3.4.0</version>
            </plugin>
            <plugin>
               <artifactId>maven-resources-plugin</artifactId>
               <version>3.3.1</version>
            </plugin>
            <plugin>
               <artifactId>maven-compiler-plugin</artifactId>
               <version>3.13.0</version>
            </plugin>
            <plugin>
               <artifactId>maven-surefire-plugin</artifactId>
               <version>3.3.0</version>
            </plugin>
            <plugin>
               <artifactId>maven-war-plugin</artifactId>
               <version>3.4.0</version>
            </plugin>
            <plugin>
            <artifactId>maven-install-plugin</artifactId>
               <version>3.1.2</version>
            </plugin>
            <plugin>
               <artifactId>maven-deploy-plugin</artifactId>
               <version>3.1.2</version>
            </plugin>
         </plugins>
      </pluginManagement>
   </build>
</project>

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.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class UserController {
	
   @GetMapping("/user/{name}")
   public @ResponseBody User getUser(@PathVariable("name") String name) {

      User user = new User();

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

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.

hello-servlet.xml

<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 = "com.tutorialspoint" />
   <mvc:annotation-driven />
</beans>

Output

Once you are done with creating source and configuration files, export your application. Right click on your application, use Run As → Maven Install option and save your hello.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/hello/user/mahesh and we will see the following screen.