jackson jaxb annotations support in Spring - spring

Question

i'm looking for the simplest way of adding jaxb annotations support to jackson.
Jackson is added now to Spring by <mvc:annotation-driven/>. I need that by #ResponseBody annotation the Object is converted to xml or json dependently to the media type.
I'm new in spring-mvc so doesn't understand well yet how things work. Thanks.

Answer 1

Okay, I assume you want to be able to return both XML and JSON. To do this you need to create MessageConverters for both formats.
The XML message converter:
<bean id="xmlConverter"
class="org.springframework.http.converter.xml.MarshallingHttpMessageConverter">
<constructor-arg>
<oxm:jaxb2-marshaller id="jaxb2Marshaller">
<!-- you must either bind your JAXB annotated classes here -->
<!-- OR provide a jaxb.index and use contextPath -->
<oxm:class-to-be-bound name="com.mycompany.MyClass"/>
</oxm:jaxb2-marshaller>
</constructor-arg>
<property name="supportedMediaTypes">
<list>
<bean class="org.springframework.http.MediaType">
<constructor-arg index="0" value="application"/>
<constructor-arg index="1" value="xml"/>
<constructor-arg index="2" value="UTF-8"/>
</bean>
</list>
</property>
</bean>
The JSON message converter, which uses the JAXB annotations:
<bean id="jaxbAnnotationInspector"
class="org.codehaus.jackson.xc.JaxbAnnotationIntrospector"/>
<bean id="jacksonObjectMapper" class="org.codehaus.jackson.map.ObjectMapper">
<property name="annotationIntrospector" ref="jaxbAnnotationInspector"/>
</bean>
<bean id="jsonConverter"
class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
<property name="objectMapper">
<bean ref="jacksonObjectMapper"/>
</property>
<property name="supportedMediaTypes">
<list>
<bean class="org.springframework.http.MediaType">
<constructor-arg index="0" value="application"/>
<constructor-arg index="1" value="json"/>
<constructor-arg index="2" value="UTF-8"/>
</bean>
</list>
</property>
</bean>
And finally, the AnnotationMethodHandlerAdapter, which will convert the responses to the appropriate content type, depending upon the accept headers:
<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<ref bean="xmlConverter"/>
<ref bean="jsonConverter"/>
</list>
</property>
</bean>
Note that the JAXB support in jackson isn't 100% complete or correct all the time, but the developers are really good at fixing bugs and responding to error reports.