Method build

arrow-array/src/builder/union_builder.rs:284–318

Builds this builder creating a new `UnionArray`.

(self)

    /// Builds this builder creating a new `UnionArray`.
    pub fn build(self) -> Result<UnionArray, ArrowError> {
        let mut children = Vec::with_capacity(self.fields.len());
        let union_fields = self
            .fields
            .into_iter()
            .map(
                |(
                    name,
                    FieldData {
                        type_id,
                        data_type,
                        mut values_buffer,
                        slots,
                        mut null_buffer_builder,
                    },
                )| {
                    let array_ref = make_array(unsafe {
                        ArrayDataBuilder::new(data_type.clone())
                            .add_buffer(values_buffer.finish())
                            .len(slots)
                            .nulls(null_buffer_builder.finish())
                            .build_unchecked()
                    });
                    children.push(array_ref);
                    (type_id, Arc::new(Field::new(name, data_type, false)))
                },
            )
            .collect();
        UnionArray::try_new(
            union_fields,
            self.type_id_builder.into(),
            self.value_offset_builder.map(Into::into),
            children,
        )
    }

    /// Builds this builder creating a new `UnionArray` without consuming the builder.
    ///