See: Description
| Class | Description |
|---|---|
| JoinMapper<K,V> |
Maps records from two different data sets to partitions so all the records laying in the same partition can be grouped.
MultipleInputsFileSplitInputFormat needs to be set as the job's input format in order to read two different data sets.Partitions are read from a previously generated PartitoningResult file which is expected to be found in the distributed cache with the symbolic link ConfigParams.PARTITIONING_RESULT.For information about generating a PartitioningResult file see Partitioning. |
| JoinOutputCommitter |
Cleans and commits the data output by the different
JoinReducer instances. |
| JoinPartitioner |
Implementation of
Partitioner. |
| JoinReducer |
Processes groups of records from two different data sets that belong to the same partition and determines which pair of records meet the spatial interaction defined in the job's
SpatialOperationConfig.Each reducer task is meant to process all the records for one partition which are expected to be grouped using JoinGroupGroupComparator and the values should be sorted using JoinGroupKeyComparator. |