/*
***************************************************************************************
* 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.pattern.observer;
import com.espertech.esper.client.EPException;
import com.espertech.esper.epl.expression.core.ExprNode;
import com.espertech.esper.epl.expression.core.ExprValidationContext;
import com.espertech.esper.pattern.*;
import com.espertech.esper.schedule.ScheduleParameterException;
import com.espertech.esper.schedule.ScheduleSpec;
import com.espertech.esper.schedule.ScheduleSpecUtil;
import com.espertech.esper.util.MetaDefItem;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Serializable;
import java.util.List;
/**
* Factory for 'crontab' observers that indicate truth when a time point was reached.
*/
public class TimerAtObserverFactory implements ObserverFactory, MetaDefItem, Serializable {
private static final long serialVersionUID = -4463261229142331396L;
/**
* Parameters.
*/
protected List<ExprNode> parameters;
/**
* Convertor.
*/
protected transient MatchedEventConvertor convertor;
/**
* The schedule specification for the timer-at.
*/
protected ScheduleSpec spec = null;
public void setObserverParameters(List<ExprNode> parameters, MatchedEventConvertor convertor, ExprValidationContext validationContext) throws ObserverParameterException {
ObserverParameterUtil.validateNoNamedParameters("timer:at", parameters);
if (log.isDebugEnabled()) {
log.debug(".setObserverParameters " + parameters);
}
if ((parameters.size() < 5) || (parameters.size() > 7)) {
throw new ObserverParameterException("Invalid number of parameters for timer:at");
}
this.parameters = parameters;
this.convertor = convertor;
// if all parameters are constants, lets try to evaluate and build a schedule for early validation
boolean allConstantResult = true;
for (ExprNode param : parameters) {
if (!param.isConstantResult()) {
allConstantResult = false;
}
}
if (allConstantResult) {
try {
List<Object> observerParameters = PatternExpressionUtil.evaluate("Timer-at observer", new MatchedEventMapImpl(convertor.getMatchedEventMapMeta()), parameters, convertor, null);
spec = ScheduleSpecUtil.computeValues(observerParameters.toArray());
} catch (ScheduleParameterException e) {
throw new ObserverParameterException("Error computing crontab schedule specification: " + e.getMessage(), e);
}
}
}
public ScheduleSpec computeSpec(MatchedEventMap beginState, PatternAgentInstanceContext context) {
if (spec != null) {
return spec;
}
List<Object> observerParameters = PatternExpressionUtil.evaluate("Timer-at observer", beginState, parameters, convertor, context.getAgentInstanceContext());
try {
return ScheduleSpecUtil.computeValues(observerParameters.toArray());
} catch (ScheduleParameterException e) {
throw new EPException("Error computing crontab schedule specification: " + e.getMessage(), e);
}
}
public EventObserver makeObserver(PatternAgentInstanceContext context, MatchedEventMap beginState, ObserverEventEvaluator observerEventEvaluator,
EvalStateNodeNumber stateNodeId, Object observerState, boolean isFilterChildNonQuitting) {
return new TimerAtObserver(computeSpec(beginState, context), beginState, observerEventEvaluator);
}
public boolean isNonRestarting() {
return false;
}
private static final Logger log = LoggerFactory.getLogger(TimerAtObserverFactory.class);
}