Spring REST XML and JSON Example

I thought to write an article about Spring REST XML and JSON application where I will show you how easily we can extend the existing application to support XML. Since I will be making changes to the existing project, make sure you first download it from below link.

Download Spring Restful Webservice Project

Now do following changes to spring bean configuration file.

1. Define a bean of type Jaxb2RootElementHttpMessageConverter.

   <beans:bean id="xmlMessageConverter" class="org.springframework.http.converter.xml.Jaxb2RootElementHttpMessageConverter">
   </beans:bean>
   

2. Add above configured bean to RequestMappingHandlerAdapter property messageConverters.

   <beans:bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
   <beans:property name="messageConverters">
   	<beans:list>
   		<beans:ref bean="jsonMessageConverter"/>
   		<beans:ref bean="xmlMessageConverter"/>
   	</beans:list>
   </beans:property>
   </beans:bean>
   

After above changes, our final spring bean configuration file will look like below. servlet-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="https://www.springframework.org/schema/mvc"
	xmlns:xsi="https://www.w3.org/2001/XMLSchema-instance"
	xmlns:beans="https://www.springframework.org/schema/beans"
	xmlns:context="https://www.springframework.org/schema/context"
	xsi:schemaLocation="https://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd
		https://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans.xsd
		https://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

	<!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure -->
	
	<!-- Enables the Spring MVC @Controller programming model -->
	<annotation-driven />

	<!-- Handles HTTP GET requests for /resources/** by efficiently serving up static resources in the ${webappRoot}/resources directory -->
	<resources mapping="/resources/**" location="/resources/" />

	<!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory -->
	<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<beans:property name="prefix" value="/WEB-INF/views/" />
		<beans:property name="suffix" value=".jsp" />
	</beans:bean>
	
	<!-- Configure to plugin JSON as request and response in method handler -->
	<beans:bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
		<beans:property name="messageConverters">
			<beans:list>
				<beans:ref bean="jsonMessageConverter"/>
				<beans:ref bean="xmlMessageConverter"/>
			</beans:list>
		</beans:property>
	</beans:bean>
	
	<!-- Configure bean to convert JSON to POJO and vice versa -->
	<beans:bean id="jsonMessageConverter" class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
	</beans:bean>	
	
	<beans:bean id="xmlMessageConverter" class="org.springframework.http.converter.xml.Jaxb2RootElementHttpMessageConverter">
	</beans:bean>
	
	<context:component-scan base-package="com.journaldev.spring.controller" />
	
</beans:beans>

We know that for working with JAXB marshalling for a class, we need to annotate it with @XmlRootElement annotation. So add this to our Employee model class. Employee.java

@XmlRootElement
public class Employee implements Serializable{

//no change in code
}

That’s it, we are DONE. Our Spring application will support both JSON as well as XML. It will even support XML request with JSON response and vice versa. Below are some of the screenshots showing this in action. NOTE: I am using Postman Chrome application for this, you can use any rest client for this testing. 1. XML Response: Make sure you pass Accept header as “application/xml”. 2. JSON Response: Make sure you pass Accept header as “application/json”. 3. XML Request with JSON Response: Make sure Accept header is “application/json” and Content-Type header is “text/xml” as shown in below images. That’s all for Spring Restful web services example for supporting both XML and JSON. You can see how easy it is to extend Spring framework, this is one of the major reason of spring framework popularity.