private @Nullable NullabilityAnnotationInfo isAccessorNullableAccessor(Element element) {
    for (AnnotationMirror annotation : element.getAnnotationMirrors()) {
      TypeElement annotationElement = (TypeElement) annotation.getAnnotationType().asElement();
      Name simpleName = annotationElement.getSimpleName();
      Name qualifiedName = annotationElement.getQualifiedName();
      if (isNullableAnnotation(simpleName, qualifiedName)) {
        return ImmutableNullabilityAnnotationInfo.of(annotationElement);
      }
    }
    return null;
  }
Initialized Validates things that were not validated otherwise
@param instantiationCreator can instantiate encodings
value-processor/src/org/immutables/value/processor/meta/ValueAttribute.java