ValueAggregator (Hadoop 0.20.2-cdh3u4 API)
Date: 2012-05-07

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## org.apache.hadoop.mapred.lib.aggregate
Interface ValueAggregator

All Known Implementing Classes:
  DoubleValueSum, LongValueMax, LongValueMin, LongValueSum, StringValueMax, StringValueMin, UniqValueCount, ValueHistogram

    public interface ValueAggregator

This interface defines the minimal protocol for value aggregators.

Method Summary
`void` | `addNextValue(Object val)` add a value to the aggregator
`ArrayList` | `getCombinerOutput()`
`String` | `getReport()`
`void` | `reset()` reset the aggregator

Method Detail

### addNextValue

    void addNextValue(Object val)

  add a value to the aggregator

  Parameters:
    `val` - the value to be added

### reset

    void reset()

  reset the aggregator

### getReport

    String getReport()

  Returns:
    the string representation of the agregator

### getCombinerOutput

    ArrayList getCombinerOutput()

  Returns:
    an array of values as the outputs of the combiner.

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