private static @Nullable PsiMethod findAttributeMethod(PsiNameValuePair attribute) {
    PsiReference ref = attribute.getReference();
    if (ref == null) return null;
    PsiElement target = ref.resolve();
    if (PsiUtil.isAnnotationMethod(target)) {
      return (PsiAnnotationMethod)target;
    }
    return null;
  }
private static @Nullable PsiMethod findAttributeMethod(PsiNameValuePair attribute)