Package org.apache.beam.sdk.transforms

Class FlatMapElements.FlatMapWithFailures<InputT,OutputT,FailureT>

java.lang.Object
org.apache.beam.sdk.transforms.PTransform<PCollection<InputT>,WithFailures.Result<PCollection<OutputT>,FailureT>>
org.apache.beam.sdk.transforms.FlatMapElements.FlatMapWithFailures<InputT,OutputT,FailureT>
All Implemented Interfaces:
Serializable, HasDisplayData
Enclosing class:
FlatMapElements<InputT,OutputT>
public static class FlatMapElements.FlatMapWithFailures<InputT,OutputT,FailureT> extends PTransform<PCollection<InputT>,WithFailures.Result<PCollection<OutputT>,FailureT>>
A PTransform that adds exception handling to FlatMapElements.
See Also:

  • Method Details

    • exceptionsVia

      public FlatMapElements.FlatMapWithFailures<InputT,OutputT,FailureT> exceptionsVia(ProcessFunction<WithFailures.ExceptionElement<InputT>,FailureT> exceptionHandler)
      Returns a new FlatMapElements.FlatMapWithFailures transform that catches exceptions raised while mapping elements, passing the raised exception instance and the input element being processed through the given exceptionHandler and emitting the result to a failure collection.

      Example usage: 

      
 Result<PCollection<String>, String>> result = words.apply(
     FlatMapElements
         .into(TypeDescriptors.strings())
         // Could throw ArrayIndexOutOfBoundsException
         .via((String line) -> Arrays.asList(Arrays.copyOfRange(line.split(" "), 1, 5)))
         .exceptionsInto(TypeDescriptors.strings())
         .exceptionsVia((ExceptionElement<String> ee) -> ee.exception().getMessage()));
 PCollection<String> output = result.output();
 PCollection<String> failures = result.failures();

    • expand

      public WithFailures.Result<PCollection<OutputT>,FailureT> expand(PCollection<InputT> input)
      Description copied from class: PTransform
      Override this method to specify how this 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).

      Specified by:
      expand in class PTransform<PCollection<InputT>,WithFailures.Result<PCollection<OutputT>,FailureT>>

    • populateDisplayData

      public void populateDisplayData(DisplayData.Builder builder)
      Description copied from class: PTransform
      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 PTransform<PCollection<InputT>,WithFailures.Result<PCollection<OutputT>,FailureT>>
      Parameters:
      builder - The builder to populate with display data.
      See Also: