Class RepeatedArrayFactory

cpp/src/arrow/array/util.cc:598–896

};

class RepeatedArrayFactory {
 public:
  RepeatedArrayFactory(MemoryPool* pool, const Scalar& scalar, int64_t length)
      : pool_(pool), scalar_(scalar), length_(length) {}

  template <typename T>
  const auto& scalar() const {
    return checked_cast<const typename TypeTraits<T>::ScalarType&>(scalar_);
  }

  Result<std::shared_ptr<Array>> Create() {
    RETURN_NOT_OK(VisitTypeInline(*scalar_.type, this));
    return out_;
  }

  Status Visit(const NullType& type) {
    DCHECK(false);  // already forwarded to MakeArrayOfNull
    return Status::OK();
  }

  Status Visit(const BooleanType&) {
    ARROW_ASSIGN_OR_RAISE(auto buffer, AllocateBitmap(length_, pool_));
    bit_util::SetBitsTo(buffer->mutable_data(), 0, length_,
                        checked_cast<const BooleanScalar&>(scalar_).value);
    out_ = std::make_shared<BooleanArray>(length_, buffer);
    return Status::OK();
  }

  template <typename T>
  enable_if_t<is_number_type<T>::value || is_temporal_type<T>::value, Status> Visit(
      const T&) {
    auto value = scalar<T>().value;
    return FinishFixedWidth(&value, sizeof(value));
  }

  Status Visit(const FixedSizeBinaryType& type) {
    auto value = checked_cast<const FixedSizeBinaryScalar&>(scalar_).value;
    return FinishFixedWidth(value->data(), type.byte_width());
  }

  template <typename T>
  enable_if_decimal<T, Status> Visit(const T&) {
    auto value = scalar<T>().value.ToBytes();
    return FinishFixedWidth(value.data(), value.size());
  }

  Status Visit(const Decimal256Type&) {
    auto value = checked_cast<const Decimal256Scalar&>(scalar_).value.ToBytes();
    return FinishFixedWidth(value.data(), value.size());
  }

  template <typename T>
  enable_if_base_binary<T, Status> Visit(const T&) {
    const std::shared_ptr<Buffer>& value = scalar<T>().value;
    std::shared_ptr<Buffer> values_buffer, offsets_buffer;
    RETURN_NOT_OK(CreateBufferOf(value->data(), value->size(), &values_buffer));
    auto size = static_cast<typename T::offset_type>(value->size());
    RETURN_NOT_OK(CreateOffsetsBuffer(size, &offsets_buffer));