/*
***************************************************************************************
* 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.property;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.client.FragmentEventType;
import com.espertech.esper.epl.expression.core.ExprEvaluator;
import com.espertech.esper.epl.expression.core.ExprEvaluatorContext;
import com.espertech.esper.epl.expression.core.ExprNodeUtility;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.ArrayDeque;
import java.util.Collection;
import java.util.List;
/**
* A property evaluator that returns a full row of events for each stream, i.e. flattened inner-join results for
* property-upon-property.
*/
public class PropertyEvaluatorAccumulative {
private static final Logger log = LoggerFactory.getLogger(PropertyEvaluatorAccumulative.class);
private final ContainedEventEval[] containedEventEvals;
private final FragmentEventType[] fragmentEventType;
private final ExprEvaluator[] whereClauses;
private final int lastLevel;
private final int levels;
private final List<String> propertyNames;
/**
* Ctor.
*
* @param containedEventEvals property getters or other evaluators
* @param fragmentEventType property fragment types
* @param whereClauses filters, if any
* @param propertyNames the property names that are staggered
*/
public PropertyEvaluatorAccumulative(ContainedEventEval[] containedEventEvals, FragmentEventType[] fragmentEventType, ExprEvaluator[] whereClauses, List<String> propertyNames) {
this.fragmentEventType = fragmentEventType;
this.containedEventEvals = containedEventEvals;
this.whereClauses = whereClauses;
lastLevel = fragmentEventType.length - 1;
levels = fragmentEventType.length + 1;
this.propertyNames = propertyNames;
}
/**
* Returns the accumulative events for the input event.
*
* @param theEvent is the input event
* @param exprEvaluatorContext expression evaluation context
* @return events per stream for each row
*/
public ArrayDeque<EventBean[]> getAccumulative(EventBean theEvent, ExprEvaluatorContext exprEvaluatorContext) {
ArrayDeque<EventBean[]> resultEvents = new ArrayDeque<EventBean[]>();
EventBean[] eventsPerStream = new EventBean[levels];
eventsPerStream[0] = theEvent;
populateEvents(eventsPerStream, theEvent, 0, resultEvents, exprEvaluatorContext);
if (resultEvents.isEmpty()) {
return null;
}
return resultEvents;
}
private void populateEvents(EventBean[] eventsPerStream, EventBean branch, int level, Collection<EventBean[]> events, ExprEvaluatorContext exprEvaluatorContext) {
try {
Object result = containedEventEvals[level].getFragment(branch, eventsPerStream, exprEvaluatorContext);
if (fragmentEventType[level].isIndexed()) {
EventBean[] fragments = (EventBean[]) result;
if (level == lastLevel) {
if (whereClauses[level] != null) {
for (EventBean theEvent : fragments) {
eventsPerStream[level + 1] = theEvent;
if (ExprNodeUtility.applyFilterExpression(whereClauses[level], eventsPerStream, exprEvaluatorContext)) {
EventBean[] eventsPerRow = new EventBean[levels];
System.arraycopy(eventsPerStream, 0, eventsPerRow, 0, levels);
events.add(eventsPerRow);
}
}
} else {
for (EventBean theEvent : fragments) {
eventsPerStream[level + 1] = theEvent;
EventBean[] eventsPerRow = new EventBean[levels];
System.arraycopy(eventsPerStream, 0, eventsPerRow, 0, levels);
events.add(eventsPerRow);
}
}
} else {
if (whereClauses[level] != null) {
for (EventBean next : fragments) {
eventsPerStream[level + 1] = next;
if (ExprNodeUtility.applyFilterExpression(whereClauses[level], eventsPerStream, exprEvaluatorContext)) {
populateEvents(eventsPerStream, next, level + 1, events, exprEvaluatorContext);
}
}
} else {
for (EventBean next : fragments) {
eventsPerStream[level + 1] = next;
populateEvents(eventsPerStream, next, level + 1, events, exprEvaluatorContext);
}
}
}
} else {
EventBean fragment = (EventBean) result;
if (level == lastLevel) {
if (whereClauses[level] != null) {
eventsPerStream[level + 1] = fragment;
if (ExprNodeUtility.applyFilterExpression(whereClauses[level], eventsPerStream, exprEvaluatorContext)) {
EventBean[] eventsPerRow = new EventBean[levels];
System.arraycopy(eventsPerStream, 0, eventsPerRow, 0, levels);
events.add(eventsPerRow);
}
} else {
eventsPerStream[level + 1] = fragment;
EventBean[] eventsPerRow = new EventBean[levels];
System.arraycopy(eventsPerStream, 0, eventsPerRow, 0, levels);
events.add(eventsPerRow);
}
} else {
if (whereClauses[level] != null) {
eventsPerStream[level + 1] = fragment;
if (ExprNodeUtility.applyFilterExpression(whereClauses[level], eventsPerStream, exprEvaluatorContext)) {
populateEvents(eventsPerStream, fragment, level + 1, events, exprEvaluatorContext);
}
} else {
eventsPerStream[level + 1] = fragment;
populateEvents(eventsPerStream, fragment, level + 1, events, exprEvaluatorContext);
}
}
}
} catch (RuntimeException ex) {
log.error("Unexpected error evaluating property expression for event of type '" +
branch.getEventType().getName() +
"' and property '" +
propertyNames.get(level + 1) + "': " + ex.getMessage(), ex);
}
}
}