I am using Spring 4.1.6 and Jackson FasterXML 2.1.4.
<mvc:annotation-driven>
<mvc:message-converters>
<bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
<property name="objectMapper">
<bean class="com.fasterxml.jackson.databind.ObjectMapper">
<!-- ?????null??-->
<property name="serializationInclusion" value="NON_NULL"/>
</bean>
</property>
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
this works at my applicationContext.xml configration