/*
***************************************************************************************
* Copyright (C) 2006 EsperTech, Inc. All rights reserved. *
* http://www.espertech.com/esper *
* 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.aggregator.AggregationMethod;
import com.espertech.esper.epl.expression.core.ExprEvaluator;
import com.espertech.esper.epl.expression.core.ExprEvaluatorContext;
import com.espertech.esper.metrics.instrumentation.InstrumentationHelper;
import java.util.*;
/**
* Implementation for handling aggregation with grouping by group-keys.
*/
public class AggSvcGroupByRefcountedNoAccessImpl extends AggregationServiceBaseGrouped {
// maintain for each group a row of aggregator states that the expression node canb pull the data from via index
protected Map<Object, AggregationMethodRow> aggregatorsPerGroup;
// maintain a current row for random access into the aggregator state table
// (row=groups, columns=expression nodes that have aggregation functions)
private AggregationMethod[] currentAggregatorRow;
private Object currentGroupKey;
private List<Object> removedKeys;
/**
* Ctor.
*
* @param evaluators - evaluate the sub-expression within the aggregate function (ie. sum(4*myNum))
* @param prototypes - collect the aggregation state that evaluators evaluate to, act as prototypes for new aggregations
* aggregation states for each group
*/
public AggSvcGroupByRefcountedNoAccessImpl(ExprEvaluator[] evaluators,
AggregationMethodFactory[] prototypes) {
super(evaluators, prototypes);
this.aggregatorsPerGroup = new HashMap<Object, AggregationMethodRow>();
removedKeys = new ArrayList<Object>();
}
public void clearResults(ExprEvaluatorContext exprEvaluatorContext) {
aggregatorsPerGroup.clear();
}
public void applyEnter(EventBean[] eventsPerStream, Object groupByKey, ExprEvaluatorContext exprEvaluatorContext) {
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().qAggregationGroupedApplyEnterLeave(true, aggregators.length, 0, groupByKey);
}
handleRemovedKeys();
AggregationMethodRow row = aggregatorsPerGroup.get(groupByKey);
// The aggregators for this group do not exist, need to create them from the prototypes
AggregationMethod[] groupAggregators;
if (row == null) {
groupAggregators = AggSvcGroupByUtil.newAggregators(aggregators);
row = new AggregationMethodRow(1, groupAggregators);
aggregatorsPerGroup.put(groupByKey, row);
} else {
groupAggregators = row.getMethods();
row.increaseRefcount();
}
// For this row, evaluate sub-expressions, enter result
currentAggregatorRow = groupAggregators;
for (int i = 0; i < evaluators.length; i++) {
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().qAggNoAccessEnterLeave(true, i, groupAggregators[i], aggregators[i].getAggregationExpression());
}
Object columnResult = evaluators[i].evaluate(eventsPerStream, true, exprEvaluatorContext);
groupAggregators[i].enter(columnResult);
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().aAggNoAccessEnterLeave(true, i, groupAggregators[i]);
}
}
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().aAggregationGroupedApplyEnterLeave(true);
}
}
public void applyLeave(EventBean[] eventsPerStream, Object groupByKey, ExprEvaluatorContext exprEvaluatorContext) {
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().qAggregationGroupedApplyEnterLeave(false, aggregators.length, 0, groupByKey);
}
AggregationMethodRow row = aggregatorsPerGroup.get(groupByKey);
// The aggregators for this group do not exist, need to create them from the prototypes
AggregationMethod[] groupAggregators;
if (row != null) {
groupAggregators = row.getMethods();
} else {
groupAggregators = AggSvcGroupByUtil.newAggregators(aggregators);
row = new AggregationMethodRow(1, groupAggregators);
aggregatorsPerGroup.put(groupByKey, row);
}
// For this row, evaluate sub-expressions, enter result
currentAggregatorRow = groupAggregators;
for (int i = 0; i < evaluators.length; i++) {
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().qAggNoAccessEnterLeave(false, i, groupAggregators[i], aggregators[i].getAggregationExpression());
}
Object columnResult = evaluators[i].evaluate(eventsPerStream, false, exprEvaluatorContext);
groupAggregators[i].leave(columnResult);
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().aAggNoAccessEnterLeave(false, i, groupAggregators[i]);
}
}
row.decreaseRefcount();
if (row.getRefcount() <= 0) {
removedKeys.add(groupByKey);
}
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().aAggregationGroupedApplyEnterLeave(false);
}
}
public void setCurrentAccess(Object groupByKey, int agentInstanceId, AggregationGroupByRollupLevel rollupLevel) {
AggregationMethodRow row = aggregatorsPerGroup.get(groupByKey);
if (row != null) {
currentAggregatorRow = row.getMethods();
} else {
currentAggregatorRow = null;
}
if (currentAggregatorRow == null) {
currentAggregatorRow = AggSvcGroupByUtil.newAggregators(aggregators);
}
currentGroupKey = groupByKey;
}
public Object getValue(int column, int agentInstanceId, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext) {
return currentAggregatorRow[column].getValue();
}
public Collection<EventBean> getCollectionOfEvents(int column, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context) {
return null;
}
public Collection<Object> getCollectionScalar(int column, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context) {
return null;
}
public EventBean getEventBean(int column, EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context) {
return null;
}
public void setRemovedCallback(AggregationRowRemovedCallback callback) {
// not applicable
}
public void accept(AggregationServiceVisitor visitor) {
visitor.visitAggregations(aggregatorsPerGroup.size(), aggregatorsPerGroup);
}
public void acceptGroupDetail(AggregationServiceVisitorWGroupDetail visitor) {
visitor.visitGrouped(aggregatorsPerGroup.size());
for (Map.Entry<Object, AggregationMethodRow> entry : aggregatorsPerGroup.entrySet()) {
visitor.visitGroup(entry.getKey(), entry.getValue());
}
}
public boolean isGrouped() {
return true;
}
public Object getGroupKey(int agentInstanceId) {
return currentGroupKey;
}
protected void handleRemovedKeys() {
// we collect removed keys lazily on the next enter to reduce the chance of empty-group queries creating empty aggregators temporarily
if (!removedKeys.isEmpty()) {
for (Object removedKey : removedKeys) {
aggregatorsPerGroup.remove(removedKey);
}
removedKeys.clear();
}
}
public Collection<Object> getGroupKeys(ExprEvaluatorContext exprEvaluatorContext) {
handleRemovedKeys();
return aggregatorsPerGroup.keySet();
}
}