org.apache.flink.streaming.api.operators

Interface Output<T>

Type Parameters:

T - The type of the elements that can be emitted.

All Superinterfaces:

org.apache.flink.util.Collector<T>

All Known Implementing Classes:

AbstractStreamOperator.CountingOutput, CopyingDirectedOutput, DirectedOutput, RecordWriterOutput

@PublicEvolving
public interface Output<T>
extends org.apache.flink.util.Collector<T>

A StreamOperator is supplied with an object of this interface that can be used to emit elements and other messages, such as barriers and watermarks, from an operator.

Method Summary

Modifier and Type	Method and Description
void	emitWatermark(Watermark mark) Emits a Watermark from an operator.

Methods inherited from interface org.apache.flink.util.Collector

close, collect

Method Detail

emitWatermark

void emitWatermark(Watermark mark)

Emits a Watermark from an operator. This watermark is broadcast to all downstream operators.

A watermark specifies that no element with a timestamp lower or equal to the watermark timestamp will be emitted in the future.