/**************************************************************************************
* Copyright (C) 2008 EsperTech, Inc. All rights reserved. *
* http://esper.codehaus.org *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
**************************************************************************************/
package com.espertech.esper.epl.agg.aggregator;
/**
* Sum for any number value.
*/
public class AggregatorSumNumInteger implements AggregationMethod
{
protected int sum;
protected long numDataPoints;
public void clear()
{
sum = 0;
numDataPoints = 0;
}
public void enter(Object object)
{
if (object == null)
{
return;
}
numDataPoints++;
Number number = (Number) object;
sum += number.intValue();
}
public void leave(Object object)
{
if (object == null)
{
return;
}
numDataPoints--;
Number number = (Number) object;
sum -= number.intValue();
}
public Object getValue()
{
if (numDataPoints == 0)
{
return null;
}
return sum;
}
public Class getValueType()
{
return Integer.class;
}
}