V
- the type of the values in the input PCollection
, and the type of the elements
in the output PCollection
public class Values<V> extends PTransform<PCollection<? extends KV<?,V>>,PCollection<V>>
Values<V>
takes a PCollection
of KV<K, V>
s and returns a PCollection<V>
of the values.
Example of use:
PCollection<KV<String, Long>> wordCounts = ...;
PCollection<Long> counts = wordCounts.apply(Values.<Long>create());
Each output element has the same timestamp and is in the same windows as its corresponding
input element, and the output PCollection
has the same WindowFn
associated with it as the input.
See also Keys
.
name
Modifier and Type | Method and Description |
---|---|
static <V> Values<V> |
create()
Returns a
Values<V> PTransform . |
PCollection<V> |
expand(PCollection<? extends KV<?,V>> in)
Override this method to specify how this
PTransform should be expanded on the given
InputT . |
compose, getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, populateDisplayData, toString, validate
public static <V> Values<V> create()
Values<V>
PTransform
.V
- the type of the values in the input PCollection
, and the type of the
elements in the output PCollection
public PCollection<V> expand(PCollection<? extends KV<?,V>> in)
PTransform
PTransform
should be expanded on the given
InputT
.
NOTE: This method should not be called directly. Instead apply the PTransform
should
be applied to the InputT
using the apply
method.
Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).
expand
in class PTransform<PCollection<? extends KV<?,V>>,PCollection<V>>