title: Spring Boot REST mapping conflict event in different controller
body: <p>I have two Rest controllers in my Spring boot(1.4.0 RELEASE) app:</p>
  
  <pre><code>@RestController("/ctrl")
  public class TestController {
      @GetMapping
      public void test() {
  
      }
  }
  
  
  @RestController("/ctrl2")
  public class TestController2 {
      @GetMapping
      public void test() {
  
      }
  }
  </code></pre>
  
  <p>When I run the Spring boot app:</p>
  
  <pre><code>Caused by: java.lang.IllegalStateException: Ambiguous mapping. Cannot map '/ctrl2' method 
  public void com.xxx.controller.TestController2.test()
  to {[],methods=[GET]}: There is already '/ctrl' bean method
  public void com.xxx.controller.TestController.test() mapped.
  </code></pre>
  
  <p>If I delete one controller, everything will be fine and the app can start well. So where is the problem?</p>