结构体 MapEncoder 

struct MapEncoder<'a> {
    map: &'a MapArray,
    keys: KeyKind<'a>,
    values: FieldEncoder<'a>,
    keys_offset: usize,
    values_offset: usize,
}

字段

map: &'a MapArray

keys: KeyKind<'a>

values: FieldEncoder<'a>

keys_offset: usize

values_offset: usize

实现

impl<'a> MapEncoder<'a>

fn try_new( map: &'a MapArray, values_nullability: Option<Nullability>, value_plan: &FieldPlan, ) -> Result<Self, ArrowError>

fn encode_map_entries<W, O>( out: &mut W, keys: &GenericStringArray<O>, keys_offset: usize, start: usize, end: usize, write_item: impl FnMut(&mut W, usize) -> Result<(), ArrowError>, ) -> Result<(), ArrowError>

where W: Write + ?Sized, O: OffsetSizeTrait,

fn encode<W: Write + ?Sized>( &mut self, out: &mut W, idx: usize, ) -> Result<(), ArrowError>