code: public AnnotatedTypeBuilder<X> addToMethod(AnnotatedMethod<? super X> method, Annotation annotation) {
         return addToMethod(method.getJavaMember(), annotation);
     }
docs: Add an annotation to the specified method. If the method is not already
  present, it will be added.
  
  @param method     the method to add the annotation to
  @param annotation the annotation to add
  @throws IllegalArgumentException if the annotation is null