PubsubIO.Read.Bound.PubsubReader (Google Cloud Dataflow SDK 1.9.1 API)

Google Cloud Dataflow SDK for Java, version 1.9.1

Warning: Dataflow SDK 1.x for Java is unsupported as of October 16, 2018. See Migrating from Dataflow SDK 1.x for Java for migration guidance.

Note: If you are using Cloud Dataflow SDK version 2.x, see the Apache Beam API reference documentation.

com.google.cloud.dataflow.sdk.io

Class PubsubIO.Read.Bound.PubsubReader

• java.lang.Object
• • com.google.cloud.dataflow.sdk.transforms.DoFn<Void,T>
  • • com.google.cloud.dataflow.sdk.io.PubsubIO.Read.Bound.PubsubReader

• All Implemented Interfaces:

  HasDisplayData, Serializable

  Enclosing class:

  PubsubIO.Read.Bound<T>

  ---

  
  

  public class PubsubIO.Read.Bound.PubsubReader
  extends DoFn<Void,T>

  Default reader when Pubsub subscription has some form of upper bound.

  TODO: Consider replacing with BoundedReadFromUnboundedSource on top of PubsubUnboundedSource.

  NOTE: This is not the implementation used when running on the Google Cloud Dataflow service in streaming mode.

  Public so can be suppressed by runners.

  See Also:

  Serialized Form

• • Nested Class Summary

    • Nested classes/interfaces inherited from class com.google.cloud.dataflow.sdk.transforms.DoFn

      DoFn.Context, DoFn.ProcessContext, DoFn.RequiresWindowAccess

  • Constructor Summary

    Constructors 

    Constructor and Description
    PubsubReader()

  • Method Summary

    All Methods Instance Methods Concrete Methods 

    Modifier and Type	Method and Description
    void	populateDisplayData(DisplayData.Builder builder) Register display data for the given transform or component.
    void	processElement(DoFn.ProcessContext c) Processes one input element.

    • Methods inherited from class com.google.cloud.dataflow.sdk.transforms.DoFn

      createAggregator, createAggregator, finishBundle, getAllowedTimestampSkew, getInputTypeDescriptor, getOutputTypeDescriptor, startBundle

    • Methods inherited from class java.lang.Object

      clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

• • Constructor Detail

    • PubsubReader

      public PubsubReader()

  • Method Detail

    • processElement

      public void processElement(DoFn.ProcessContext c)
                          throws IOException

      Description copied from class: DoFn
      Processes one input element.

      The current element of the input PCollection is returned by c.element(). It should be considered immutable. The Dataflow runtime will not mutate the element, so it is safe to cache, etc. The element should not be mutated by any of the DoFn methods, because it may be cached elsewhere, retained by the Dataflow runtime, or used in other unspecified ways.

      A value is added to the main output PCollection by DoFn.Context.output(OutputT). Once passed to output the element should be considered immutable and not be modified in any way. It may be cached elsewhere, retained by the Dataflow runtime, or used in other unspecified ways.

      Specified by:

      processElement in class DoFn<Void,T>

      Throws:

      IOException

      See Also:

      DoFn.ProcessContext

    • populateDisplayData

      public void populateDisplayData(DisplayData.Builder builder)

      Description copied from class: DoFn
      Register display data for the given transform or component.

      populateDisplayData(DisplayData.Builder) is invoked by Pipeline runners to collect display data via DisplayData.from(HasDisplayData). Implementations may call super.populateDisplayData(builder) in order to register display data in the current namespace, but should otherwise use subcomponent.populateDisplayData(builder) to use the namespace of the subcomponent.

      By default, does not register any display data. Implementors may override this method to provide their own display data.

      Specified by:

      populateDisplayData in interface HasDisplayData

      Overrides:

      populateDisplayData in class DoFn<Void,T>

      Parameters:

      builder - The builder to populate with display data.

      See Also:

      HasDisplayData