Method GetDictionary

cpp/src/arrow/compute/kernels/vector_hash.cc:423–432

  Status FlushFinal(ExecResult* out) override { return action_.FlushFinal(out); }

  Status GetDictionary(std::shared_ptr<ArrayData>* out) override {
    std::shared_ptr<NullArray> null_array;
    if (seen_null_) {
      null_array = std::make_shared<NullArray>(1);
    } else {
      null_array = std::make_shared<NullArray>(0);
    }
    *out = null_array->data();
    return Status::OK();
  }

  std::shared_ptr<DataType> value_type() const override { return type_; }