Class GafferReducer<KEY,​VALUE>

  • Direct Known Subclasses:
    AccumuloKeyValueReducer

    public abstract class GafferReducer<KEY,​VALUE>
    extends org.apache.hadoop.mapreduce.Reducer<KEY,​VALUE,​KEY,​VALUE>

    Reducer for use in bulk import of data into a Gaffer Store. It merges all values associated to the KEY by converting them into Properties and then merges those, and then converts them back to an VALUE.

    It contains an optimisation so that if there is only one value, we simply output it rather than incurring the cost of deserialising them and then reserialising them.

    • Nested Class Summary

      • Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Reducer

        org.apache.hadoop.mapreduce.Reducer.Context
    • Constructor Summary

      Constructors 
      Constructor Description
      GafferReducer()  
    • Constructor Detail

      • GafferReducer

        public GafferReducer()