/*
* *************************************************************************************
* 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.service;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.epl.agg.access.AggregationState;
import com.espertech.esper.epl.agg.access.AggregationAccessorSlotPair;
import com.espertech.esper.epl.core.MethodResolutionService;
import com.espertech.esper.epl.expression.ExprEvaluatorContext;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
/**
* Aggregation service for use when only first/last/window aggregation functions are used an none other.
*/
public class AggSvcGroupByAccessOnlyImpl implements AggregationService, AggregationResultFuture
{
private final MethodResolutionService methodResolutionService;
private final Map<Object, AggregationState[]> accessMap;
private final AggregationAccessorSlotPair[] accessors;
private final AggregationStateFactory[] accessAggSpecs;
private final boolean isJoin;
private AggregationState[] currentAcceses;
/**
* Ctor.
* @param methodResolutionService factory service for implementations
* @param accessors accessor definitions
* @param accessAggSpecs access agg specs
* @param isJoin true for join, false for single-stream
*/
public AggSvcGroupByAccessOnlyImpl(MethodResolutionService methodResolutionService,
AggregationAccessorSlotPair[] accessors,
AggregationStateFactory[] accessAggSpecs,
boolean isJoin)
{
this.methodResolutionService = methodResolutionService;
this.accessMap = new HashMap<Object, AggregationState[]>();
this.accessors = accessors;
this.accessAggSpecs = accessAggSpecs;
this.isJoin = isJoin;
}
public void applyEnter(EventBean[] eventsPerStream, Object groupKey, ExprEvaluatorContext exprEvaluatorContext)
{
AggregationState[] row = getAssertRow(exprEvaluatorContext.getAgentInstanceId(), groupKey);
for (AggregationState state : row) {
state.applyEnter(eventsPerStream, exprEvaluatorContext);
}
}
public void applyLeave(EventBean[] eventsPerStream, Object groupKey, ExprEvaluatorContext exprEvaluatorContext)
{
AggregationState[] row = getAssertRow(exprEvaluatorContext.getAgentInstanceId(), groupKey);
for (AggregationState state : row) {
state.applyLeave(eventsPerStream, exprEvaluatorContext);
}
}
public void setCurrentAccess(Object groupKey, int agentInstanceId)
{
currentAcceses = getAssertRow(agentInstanceId, groupKey);
}
public Object getValue(int column, int agentInstanceId)
{
AggregationAccessorSlotPair pair = accessors[column];
return pair.getAccessor().getValue(currentAcceses[pair.getSlot()]);
}
public Collection<EventBean> getCollection(int column, ExprEvaluatorContext context) {
AggregationAccessorSlotPair pair = accessors[column];
return pair.getAccessor().getEnumerableEvents(currentAcceses[pair.getSlot()]);
}
public EventBean getEventBean(int column, ExprEvaluatorContext context) {
AggregationAccessorSlotPair pair = accessors[column];
return pair.getAccessor().getEnumerableEvent(currentAcceses[pair.getSlot()]);
}
public void clearResults(ExprEvaluatorContext exprEvaluatorContext)
{
accessMap.clear();
}
private AggregationState[] getAssertRow(int agentInstanceId, Object groupKey) {
AggregationState[] row = accessMap.get(groupKey);
if (row != null) {
return row;
}
row = methodResolutionService.newAccesses(agentInstanceId, isJoin, accessAggSpecs, groupKey);
accessMap.put(groupKey, row);
return row;
}
public void setRemovedCallback(AggregationRowRemovedCallback callback) {
// not applicable
}
}