T - the type of the elements in the input and output
PCollections.public static class Flatten.PCollections<T> extends PTransform<PCollectionList<T>,PCollection<T>>
PTransform that flattens a PCollectionList
into a PCollection containing all the elements of all
the PCollections in its input.
Implements Flatten.pCollections().name| Modifier and Type | Method and Description |
|---|---|
PCollection<T> |
expand(PCollectionList<T> inputs)
Applies this
PTransform on the given InputT, and returns its
Output. |
protected Coder<?> |
getDefaultOutputCoder(PCollectionList<T> input)
Returns the default
Coder to use for the output of this
single-output PTransform when applied to the given input. |
getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, populateDisplayData, toString, validatepublic PCollection<T> expand(PCollectionList<T> inputs)
PTransformPTransform on the given InputT, and returns its
Output.
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<PCollectionList<T>,PCollection<T>>protected Coder<?> getDefaultOutputCoder(PCollectionList<T> input) throws CannotProvideCoderException
PTransformCoder to use for the output of this
single-output PTransform when applied to the given input.
By default, always throws.
getDefaultOutputCoder in class PTransform<PCollectionList<T>,PCollection<T>>CannotProvideCoderException - if none can be inferred.