Aggregator (Apache Geode 2.0.2)
Description: declaration: package: org.apache.geode.cache.query, interface: Aggregator

Package org.apache.geode.cache.query

# Interface Aggregator

public interface Aggregator
Behavior of a user-defined aggregator. Aggregates values and returns a result. In addition to the methods in the interface, implementing classes must have a 0-arg public constructor.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `accumulate(Object value)`
  Accumulate the next scalar value
  `void`
  `init()`
  Initialize the Aggregator
  `Object`
  `terminate()`
  Finish the aggregation and return the operation result.

- ## Method Details

  - ### init

    void init()
    Initialize the Aggregator

  - ### accumulate

    void accumulate(Object value)
    Accumulate the next scalar value
    Parameters:
      `value` - the scalar value to accumulate

  - ### terminate

    Object terminate()
    Finish the aggregation and return the operation result.
    Returns:
      Return the result scalar value