Function garrow_union_array_get_field

c_glib/arrow-glib/composite-array.cpp:1434–1462

* garrow_union_array_get_field * @array: A #GArrowUnionArray. * @i: The index of the field in the union. * * Returns: (nullable) (transfer full): The i-th field values as a * #GArrowArray or %NULL on out of range. */

 *   #GArrowArray or %NULL on out of range.
 */
GArrowArray *
garrow_union_array_get_field(GArrowUnionArray *array, gint i)
{
  auto priv = GARROW_UNION_ARRAY_GET_PRIVATE(array);
  if (!priv->fields) {
    auto arrow_array = garrow_array_get_raw(GARROW_ARRAY(array));
    auto arrow_union_array = std::static_pointer_cast<arrow::UnionArray>(arrow_array);
    auto n_fields = arrow_union_array->num_fields();
    priv->fields = g_ptr_array_sized_new(n_fields);
    g_ptr_array_set_free_func(priv->fields, g_object_unref);
    for (int i = 0; i < n_fields; ++i) {
      auto arrow_field = arrow_union_array->field(i);
      g_ptr_array_add(priv->fields, garrow_array_new_raw(&arrow_field));
    }
  }

  if (i < 0) {
    i += priv->fields->len;
  }
  if (i < 0) {
    return NULL;
  }
  if (i >= static_cast<gint>(priv->fields->len)) {
    return NULL;
  }
  auto field = static_cast<GArrowArray *>(g_ptr_array_index(priv->fields, i));
  g_object_ref(field);
  return field;
}

/**
 * garrow_union_array_get_n_fields