/**************************************************************************************
* 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.expression;
import com.espertech.esper.epl.agg.AggregationAccessor;
import com.espertech.esper.epl.agg.AggregationMethod;
import com.espertech.esper.epl.agg.AggregationMethodFactory;
import com.espertech.esper.epl.agg.AggregationSpec;
import com.espertech.esper.epl.core.MethodResolutionService;
public class ExprMedianNodeFactory implements AggregationMethodFactory
{
private final boolean isDistinct;
private final Class aggregatedValueType;
private final boolean hasFilter;
public ExprMedianNodeFactory(boolean isDistinct, Class aggregatedValueType, boolean hasFilter)
{
this.isDistinct = isDistinct;
this.aggregatedValueType = aggregatedValueType;
this.hasFilter = hasFilter;
}
public Class getResultType()
{
return Double.class;
}
public AggregationSpec getSpec(boolean isMatchRecognize)
{
return null;
}
public AggregationAccessor getAccessor()
{
throw new UnsupportedOperationException();
}
public AggregationMethod make(MethodResolutionService methodResolutionService, int agentInstanceId, int groupId, int aggregationId) {
AggregationMethod method = methodResolutionService.makeMedianAggregator(agentInstanceId, groupId, aggregationId, hasFilter);
if (!isDistinct) {
return method;
}
return methodResolutionService.makeDistinctAggregator(agentInstanceId, groupId, aggregationId, method, aggregatedValueType, hasFilter);
}
public AggregationMethodFactory getPrototypeAggregator() {
return this;
}
}