code: public static IAnnotationBinding getAnnotationBinding(
              IAnnotationBinding[] annotations, String annotationClassName) {
          if (annotations == null) {
              return null;
          }
          if (annotationClassName == null) {
              throw new NullPointerException();
          }
  
          for (IAnnotationBinding annotation : annotations) {
              String qName = annotation.getAnnotationType().getBinaryName();
              assert qName != null;
              // TODO if multiple annotations for annotationClassName exists
              if (qName.equals(annotationClassName)) {
                  return annotation;
              }
          }
          return null;
      }
docs: Return null if specified name annotation is not found.