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In addition, this FLIP also adds EndOfStreamWindows that can be used with the DataStream API to specify whether the window will end only at the end of its inputs. DataStream program (e.g. coGroup and aggregate) can take advantage of this information optimize to significantly increase throughput and reduce resource utilization as well as job throughput.

Public Interfaces

1) Add EndOfStreamWindows which is a subclass of WindowAssigner. This class allows users of the DataStream API to specify whether the computation (e.g. co-group, aggregate) should emit data only after end-of-input.

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