```
@Documented
@Retention(SOURCE)
@Target({METHOD,CONSTRUCTOR,TYPE,PARAMETER})
public @interface MainThread
```
Denotes that the annotated method should only be called on the main thread. If the annotated element is a class, then all methods in the class should be called on the main thread.
Example:
```
  @MainThread
  public void deliverResult(D data) { ... }
 
```
Note: Ordinarily, an app's main thread is also the UI thread. However, However, under special circumstances, an app's main thread might not be its UI thread; for more information, see Thread annotations.

Annotation Type MainThread