@Target(ElementType.TYPE)
@Inherited
@Retention(RetentionPolicy.RUNTIME)
public @interface Action {boolean isSingle() default true;String value() default "";String url() default "";
}@Action
class BaseController{
}public class UserController extends BaseController{public static void main(String[] args) {System.out.println(UserController.class.isAnnotationPresent(Action.class)); //trueSystem.out.println(BaseController.class.isAnnotationPresent(Action.class)); //true}
}

@Target(ElementType.TYPE)
@Inherited
@Retention(RetentionPolicy.RUNTIME)
@interface Action {boolean isSingle() default true;String value() default "";String url() default "";
}@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@interface Service {String value() default "";String url() default "";
}@Action(value="action",url="actionurl")
@Service(value="service",url="serviceurl")
class BaseController{
}public class UserController extends BaseController{public static void main(String[] args) throws ClassNotFoundException {Class<BaseController> cls = BaseController.class;Annotation[] annotations = cls.getAnnotations();for (Annotation annotation : annotations) {if(annotation instanceof Action){Action action = (Action)annotation;System.out.println(action.url());    //actionurlSystem.out.println(action.value());  //action}if(annotation instanceof Service){Service service = (Service)annotation;System.out.println(service.url());   //serviceurlSystem.out.println(service.value());  //service}}}
}

public class TestMethodAnnotations {@Target(ElementType.PARAMETER)@Retention(RetentionPolicy.RUNTIME)static @interface requestParam {String value();}@Target(ElementType.PARAMETER)@Retention(RetentionPolicy.RUNTIME)static @interface DefaultValue {String value() default "";}public void test(@requestParam("useranme") String username,@requestParam("password") @DefaultValue("1234") String password){}public static void main(String[] args) throws NoSuchMethodException, SecurityException {Class<TestMethodAnnotations> cls = TestMethodAnnotations.class;Method method = cls.getMethod("test",new Class[]{String.class,String.class});Annotation[][] anns =  method.getParameterAnnotations();for (Annotation[] annotations : anns) {for (Annotation annotation : annotations) {if(annotation instanceof requestParam){requestParam request = (requestParam)annotation;System.out.println(request.value());}if(annotation instanceof DefaultValue){DefaultValue defaultValue = (DefaultValue)annotation;System.out.println(defaultValue.value());}}}}
}