org.drools.base.accumulators
Interface AccumulateFunction

All Superinterfaces:

java.io.Serializable

All Known Implementing Classes:

AverageAccumulateFunction, CountAccumulateFunction, MaxAccumulateFunction, MinAccumulateFunction, SumAccumulateFunction

public interface AccumulateFunction
extends java.io.Serializable

An interface for accumulate external function implementations

Author:

etirelli

Method Summary

void	accumulate(java.lang.Object context, java.lang.Object value) Executes the accumulation action
java.lang.Object	createContext() Creates and returns a new context object
java.lang.Object	getResult(java.lang.Object context) Returns the current value in this accumulation session
void	init(java.lang.Object context) Initializes the accumulator
void	reverse(java.lang.Object context, java.lang.Object value) Reverses the accumulation action
boolean	supportsReverse() True if the function supports reverse.

Method Detail

createContext

java.lang.Object createContext()

Creates and returns a new context object

Returns:

init

void init(java.lang.Object context)
          throws java.lang.Exception

Initializes the accumulator

Parameters:

context -

Throws:

java.lang.Exception

accumulate

void accumulate(java.lang.Object context,
                java.lang.Object value)

Executes the accumulation action

Parameters:

context -

value -

reverse

void reverse(java.lang.Object context,
             java.lang.Object value)
             throws java.lang.Exception

Reverses the accumulation action

Parameters:

context -

value -

Throws:

java.lang.Exception

getResult

java.lang.Object getResult(java.lang.Object context)
                           throws java.lang.Exception

Returns the current value in this accumulation session

Parameters:

context -

Returns:

Throws:

java.lang.Exception

supportsReverse

boolean supportsReverse()

True if the function supports reverse. False otherwise.

Returns: