How to get JSON response using RESTful webservice in spring 3.1 - json

Question

I want to generate a JSON response of my object I write code for that but not getting success it is giving error 406 I am not using maven I am using ant
This is my controller
#Controller
public class LoginRestCtrl {
#RequestMapping(value = "/test", method=RequestMethod.GET)
#ResponseBody
public Employee checklogin(){
Employee e=new Employee();
e.setEmailId("sdosi#cur.com");
e.setId(1);
e.setPassword("a");
return e;
}
}
This is my configuration file
<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" />
<mvc:annotation-driven />
<bean class="org.springframework.web.servlet.view.tiles2.TilesConfigurer" id="tilesConfigurer">
<property name="definitions">
<list>
<value>/WEB-INF/tiles.xml</value>
</list>
</property>
</bean>
<bean class="org.springframework.web.servlet.view.UrlBasedViewResolver" id="viewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.tiles2.TilesView"/>
</bean>
<bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/WEB-INF/jsp/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
</beans>
I am calling as http://localhost:8080/SpringMVC/test but getting error 406

Answer 1

You can try following to produce JSON Rsponse. You would require Gson library, and the controller would look as follows:
#Controller
public class LoginRestCtrl {
#RequestMapping(value = "/test", method=RequestMethod.GET)
#ResponseBody
public String checklogin(){
Employee e=new Employee();
e.setEmailId("sdosi#cur.com");
e.setId(1);
e.setPassword("a");
Gson gson=new Gson();
String jsonResponse=gson.toJson(e);
return jsonResponse;
}
}
Json response looks as following:
{"emailId":"sdosi#cur.com","id":1,"password":"a"}

Answer 2

I suggest to put jackson dependencies in your pom.xml if they are not already there.
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.2.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.2.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.2.3</version>
</dependency>
If they are already there can you update your RequestMapping with
#RequestMapping(value = "/test", method=RequestMethod.GET, produces = "application/json;charset=utf-8")
This will ensure that we return a response with a json header.

Answer 3

add the following dependencies in your pom.xml file
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>1.9.12</version>
</dependency>
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20090211</version>
</dependency>
with in your spring configuration xml files add the following beans
<bean id="jacksonMessageConverter"
class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />
<bean
class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<ref bean="jacksonMessageConverter" />
</list>
</property>
</bean>
now you can use your controller as it is
#Controller
public class LoginRestCtrl {
#RequestMapping(value = "/test", method=RequestMethod.GET)
#ResponseBody
public Employee checklogin() {
Employee e=new Employee();
e.setEmailId("sdosi#cur.com");
e.setId(1);
e.setPassword("a");
return e;
}
}