/**************************************************************************************
* 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.access.AggregationAccessor;
import com.espertech.esper.epl.agg.access.AggregationStateKey;
import com.espertech.esper.epl.agg.aggregator.AggregationMethod;
import com.espertech.esper.epl.agg.service.AggregationMethodFactory;
import com.espertech.esper.epl.agg.service.AggregationStateFactory;
import com.espertech.esper.epl.core.MethodResolutionService;
public class ExprCountNodeFactory implements AggregationMethodFactory
{
private final ExprCountNode parent;
private final boolean ignoreNulls;
private final Class countedValueType;
public ExprCountNodeFactory(ExprCountNode parent, boolean ignoreNulls, Class countedValueType)
{
this.parent = parent;
this.ignoreNulls = ignoreNulls;
this.countedValueType = countedValueType;
}
public boolean isAccessAggregation() {
return false;
}
public Class getResultType()
{
return Long.class;
}
public AggregationStateKey getAggregationStateKey(boolean isMatchRecognize) {
throw new IllegalStateException("Not an access aggregation function");
}
public AggregationStateFactory getAggregationStateFactory(boolean isMatchRecognize) {
throw new IllegalStateException("Not an access aggregation function");
}
public AggregationAccessor getAccessor() {
throw new IllegalStateException("Not an access aggregation function");
}
public AggregationMethod make(MethodResolutionService methodResolutionService, int agentInstanceId, int groupId, int aggregationId) {
AggregationMethod method = methodResolutionService.makeCountAggregator(agentInstanceId, groupId, aggregationId, ignoreNulls, parent.isHasFilter());
if (!parent.isDistinct()) {
return method;
}
return methodResolutionService.makeDistinctAggregator(agentInstanceId, groupId, aggregationId, method, countedValueType, parent.isHasFilter());
}
public AggregationMethodFactory getPrototypeAggregator() {
return this;
}
public ExprNode getAggregationExpression() {
return parent;
}
}