Create (Google Cloud Dataflow SDK 1.9.1 API)

Google Cloud Dataflow SDK for Java, version 1.9.1

com.google.cloud.dataflow.sdk.transforms

Class Create<T>

  • Type Parameters:
    T - the type of the elements of the resulting PCollection


    public class Create<T>
    extends Object
    Create<T> takes a collection of elements of type T known when the pipeline is constructed and returns a PCollection<T> containing the elements.

    Example of use:

     
     Pipeline p = ...;
    
     PCollection<Integer> pc = p.apply(Create.of(3, 4, 5).withCoder(BigEndianIntegerCoder.of()));
    
     Map<String, Integer> map = ...;
     PCollection<KV<String, Integer>> pt =
         p.apply(Create.of(map)
          .withCoder(KvCoder.of(StringUtf8Coder.of(),
                                BigEndianIntegerCoder.of())));
      

    Create can automatically determine the Coder to use if all elements have the same run-time class, and a default coder is registered for that class. See CoderRegistry for details on how defaults are determined.

    If a coder can not be inferred, Create.Values.withCoder(com.google.cloud.dataflow.sdk.coders.Coder<T>) must be called explicitly to set the encoding of the resulting PCollection.

    A good use for Create is when a PCollection needs to be created without dependencies on files or other external entities. This is especially useful during testing.

    Caveat: Create only supports small in-memory datasets, particularly when submitting jobs to the Google Cloud Dataflow service.


Was this page helpful? Let us know how we did:

Send feedback about...

Cloud Dataflow
Need help? Visit our support page.