spring two method with same URL mapping
<p>I have 2 class with 2 same URL mappings:</p>

<pre><code>@RequestMapping(value = "/topics/{id}", method = RequestMethod.GET)
public ModelAndView methodA(@PathVariable(TOPIC_ID) Long topicId) {
    ...
}
//
@RequestMapping(value = "/topics/{id}", method = RequestMethod.GET)
public ModelAndView methodB(@PathVariable(TOPIC_ID) Long topicId) {
    ...
}
</code></pre>

<p>MethodB is in a class that is loaded dynamically. I want use methodA only if methodB is not available. If methodB is available the Spring uses only it.
How can I do that.</p>