/// <exception cref="System.IO.IOException"/>
private void CombineAndSpill(RawKeyValueIterator kvIter, Counters.Counter inCounter
)
{
JobConf job = jobConf;
Reducer combiner = ReflectionUtils.NewInstance(combinerClass, job);
Type keyClass = (Type)job.GetMapOutputKeyClass();
Type valClass = (Type)job.GetMapOutputValueClass();
RawComparator <K> comparator = (RawComparator <K>)job.GetCombinerKeyGroupingComparator
();
try
{
Task.CombineValuesIterator values = new Task.CombineValuesIterator(kvIter, comparator
, keyClass, valClass, job, Reporter.Null, inCounter);
while (values.More())
{
combiner.Reduce(values.GetKey(), values, combineCollector, Reporter.Null);
values.NextKey();
}
}
finally
{
combiner.Close();
}
}
/// <summary>
/// Get the user defined
/// <see cref="Org.Apache.Hadoop.IO.RawComparator{T}"/>
/// comparator for
/// grouping keys of inputs to the combiner.
/// </summary>
/// <returns>comparator set by the user for grouping values.</returns>
/// <seealso cref="Org.Apache.Hadoop.Mapreduce.Job.SetCombinerKeyGroupingComparatorClass(System.Type{T})
/// ">for details.</seealso>
public virtual RawComparator <object> GetCombinerKeyGroupingComparator()
{
return(conf.GetCombinerKeyGroupingComparator());
}