9.11 Buffers

As of Cascading 2.2, the FirstNBuffer Buffer is provided as an optimized means to determine the top N elements in a grouping.


The cascading.operation.buffer.FirstNBuffer Buffer returns the first N tuples seen in a given grouping. Unlike the cascading.pipe.assembly.FirstBy AggregateBy and cascading.operation.aggregator.First Aggregator, FirstNBuffer will stop iterating the available tuples when the top N condition is met. FirstNBuffer is used by cascading.pipe.assembly.Unique.

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