Struct arrow::array::ListBuilder

pub struct ListBuilder<T: ArrayBuilder> { /* fields omitted */ }

Array builder for ListArray

Implementations

impl<T: ArrayBuilder> ListBuilder<T>

pub fn new(values_builder: T) -> Self

Creates a new ListArrayBuilder from a given values array builder

pub fn with_capacity(values_builder: T, capacity: usize) -> Self

Creates a new ListArrayBuilder from a given values array builder capacity is the number of items to pre-allocate space for in this builder

impl<T: ArrayBuilder> ListBuilder<T> where
    T: 'static, 

pub fn values(&mut self) -> &mut T

Returns the child array builder as a mutable reference.

This mutable reference can be used to append values into the child array builder, but you must call append to delimit each distinct list value.

pub fn append(&mut self, is_valid: bool) -> Result<()>

Finish the current variable-length list array slot

pub fn finish(&mut self) -> ListArray

Builds the ListArray and reset this builder.

Trait Implementations

impl<T: ArrayBuilder> ArrayBuilder for ListBuilder<T> where
    T: 'static, 

fn as_any(&self) -> &dyn Any

Returns the builder as a non-mutable Any reference.

fn append_data(&mut self, data: &[ArrayDataRef]) -> Result<()>

Appends data from other arrays into the builder

This is most useful when concatenating arrays of the same type into a builder.

fn data_type(&self) -> DataType

Returns the data type of the builder

This is used for validating array data types in append_data

fn as_any_mut(&mut self) -> &mut dyn Any

Returns the builder as a mutable Any reference.

fn into_box_any(self: Box<Self>) -> Box<dyn Any>

Returns the boxed builder as a box of Any.

fn len(&self) -> usize

Returns the number of array slots in the builder

fn is_empty(&self) -> bool

Returns whether the number of array slots is zero

fn finish(&mut self) -> ArrayRef

Builds the array and reset this builder.

impl<T: Debug + ArrayBuilder> Debug for ListBuilder<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.