code: public static <T, A extends Annotation> String getClassAnnotationValue(Class<T> classType, Class<A> annotationType, String attributeName) {
  		String value = null;
  		Annotation annotation = classType.getAnnotation(annotationType);
  		if (annotation != null) {
  			try {
  				value = (String) annotation.annotationType().getMethod(attributeName).invoke(annotation);
  			} catch (Exception ex) {}
  		}
  		return value;
  	}
docs: Get the value of a Annotation in a class declaration.
  @param classType
  @param annotationType
  @param attributeName
  @return the value of the annotation as String or null if something goes wrong