Method Convert

cpp/src/arrow/json/converter.cc:119–146

      : PrimitiveConverter(pool, type), numeric_type_(checked_cast<const T&>(*type)) {}

  Status Convert(const std::shared_ptr<Array>& in, std::shared_ptr<Array>* out) override {
    if (in->type_id() == Type::NA) {
      return MakeArrayOfNull(out_type_, in->length(), pool_).Value(out);
    }
    const auto& dict_array = GetDictionaryArray(in);

    using Builder = typename TypeTraits<T>::BuilderType;
    Builder builder(out_type_, pool_);
    RETURN_NOT_OK(builder.Resize(dict_array.indices()->length()));

    auto visit_valid = [&](string_view repr) {
      value_type value;
      if (!arrow::internal::ParseValue(numeric_type_, repr.data(), repr.size(), &value)) {
        return GenericConversionError(*out_type_, ", couldn't parse:", repr);
      }

      builder.UnsafeAppend(value);
      return Status::OK();
    };

    auto visit_null = [&]() {
      builder.UnsafeAppendNull();
      return Status::OK();
    };

    RETURN_NOT_OK(VisitDictionaryEntries(dict_array, visit_valid, visit_null));
    return builder.Finish(out);
  }

  const T& numeric_type_;
};