Spring 3: Content Negotiation

Question

I have a REST endpoint which currently returns JSON output. I would like to modify the same endpoint to return plain text output, basically differentiate between generating application/json and text/plain Accept headers. Here's my current configuration -

servlet.xml:

<bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
    <property name="defaultContentType" value="application/json" />
    <property name="ignoreAcceptHeader" value="true" />
    <property name="order" value="0" />
    <property name="mediaTypes">
        <map>
            <entry key="text" value="text/plain" />
            <entry key="json" value="application/json" />
        </map>
    </property>

    <property name="defaultViews">
        <list>
            <ref bean="jsonView"/>
        </list>
    </property>
</bean>

<bean id="jsonView"
      class="org.springframework.web.servlet.view.json.MappingJacksonJsonView">
    <property name="contentType" value="application/json;charset=UTF-8"/>
    <property name="disableCaching" value="false"/>
</bean>

REST endpoint:

@RequestMapping(value = "/emps", method = RequestMethod.GET, produces = {"application/json"})
@ResponseStatus(HttpStatus.OK)
public @ResponseBody List<Employee> getEmpsList() throws VMException {
    final List<Employee> eList = getAllEmployees();
    return eList;
}

I tried modifying produces to {"application/json", "text/plain"}. T read through some online stuff, and since I am returning a bean, I need to use HttpMessageConverter to return text/plain output. I was able to get this work by writing two methods, one returning application/json output and other returning text/plain output. Is it even possible to combine this into single method implementation, or importantly, return result based on requested output format, i.e. json or text.

Thanks in advance for the help.

Update: Attaching image of the the postman client plugin.

Image 1: Image 2:

What actually happens when you make your changes? No change at all? A 405 or 406? — Vidya, Dec 20 '13 at 22:59
Can you show examples of what your `Accept` header looks like in your requests? — Vidya, Dec 20 '13 at 23:27
@Vidya, I have updated the question with information (screenshots). Please let me know if you need any more information. Thanks. — devang, Dec 22 '13 at 08:08
It is a little hard to read, but it looks like you have no `Accept` header in your first request. — Vidya, Dec 22 '13 at 08:34
@Vidya, the first request does not have `Accept` header, the output returned is in json format. The second has `Accept` header and I expect a text output. However, I get a `406`. — devang, Dec 22 '13 at 18:19

score 0 · Accepted Answer · answered Dec 22 '13 at 23:16

Currently you have this:

<property name="ignoreAcceptHeader" value="true" />

In fact, you don't want to ignore the Accept header. Remove that and see what happens.

Also, the mediaTypes are only relevant if you are seeking recources by extension/format, which doesn't seem to be the case here.

Spring 3: Content Negotiation

1 Answers1