pub trait ArrayBuilder:
Any
+ Send
+ Sync {
// Required methods
fn len(&self) -> usize;
fn finish(&mut self) -> ArrayRef;
fn finish_cloned(&self) -> ArrayRef;
fn as_any(&self) -> &dyn Any;
fn as_any_mut(&mut self) -> &mut dyn Any;
fn into_box_any(self: Box<Self>) -> Box<dyn Any>;
// Provided method
fn is_empty(&self) -> bool { ... }
}Expand description
Trait for dealing with different array builders at runtime
§Example
// Create
let mut data_builders: Vec<Box<dyn ArrayBuilder>> = vec![
Box::new(Float64Builder::new()),
Box::new(Int64Builder::new()),
Box::new(StringBuilder::new()),
];
// Fill
data_builders[0]
.as_any_mut()
.downcast_mut::<Float64Builder>()
.unwrap()
.append_value(3.14);
data_builders[1]
.as_any_mut()
.downcast_mut::<Int64Builder>()
.unwrap()
.append_value(-1);
data_builders[2]
.as_any_mut()
.downcast_mut::<StringBuilder>()
.unwrap()
.append_value("🍎");
// Finish
let array_refs: Vec<ArrayRef> = data_builders
.iter_mut()
.map(|builder| builder.finish())
.collect();
assert_eq!(array_refs[0].len(), 1);
assert_eq!(array_refs[1].is_null(0), false);
assert_eq!(
array_refs[2]
.as_any()
.downcast_ref::<StringArray>()
.unwrap()
.value(0),
"🍎"
);Required Methods§
Sourcefn finish_cloned(&self) -> ArrayRef
fn finish_cloned(&self) -> ArrayRef
Builds the array without resetting the underlying builder.
Sourcefn as_any(&self) -> &dyn Any
fn as_any(&self) -> &dyn Any
Returns the builder as a non-mutable Any reference.
This is most useful when one wants to call non-mutable APIs on a specific builder
type. In this case, one can first cast this into a Any, and then use
downcast_ref to get a reference on the specific builder.
Sourcefn as_any_mut(&mut self) -> &mut dyn Any
fn as_any_mut(&mut self) -> &mut dyn Any
Returns the builder as a mutable Any reference.
This is most useful when one wants to call mutable APIs on a specific builder
type. In this case, one can first cast this into a Any, and then use
downcast_mut to get a reference on the specific builder.
Sourcefn into_box_any(self: Box<Self>) -> Box<dyn Any>
fn into_box_any(self: Box<Self>) -> Box<dyn Any>
Returns the boxed builder as a box of Any.
Provided Methods§
Trait Implementations§
Source§impl ArrayBuilder for Box<dyn ArrayBuilder>
impl ArrayBuilder for Box<dyn ArrayBuilder>
Source§fn finish_cloned(&self) -> ArrayRef
fn finish_cloned(&self) -> ArrayRef
Builds the array without resetting the underlying builder.
Source§fn as_any_mut(&mut self) -> &mut dyn Any
fn as_any_mut(&mut self) -> &mut dyn Any
Returns the builder as a mutable
Any reference. Read more