/**************************************************************************************
* 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.view;
import com.espertech.esper.client.EventType;
import com.espertech.esper.core.context.util.AgentInstanceContext;
import com.espertech.esper.core.service.StatementContext;
import com.espertech.esper.epl.expression.*;
import com.espertech.esper.epl.spec.OnTriggerSetAssignment;
import com.espertech.esper.epl.variable.VariableReadWritePackage;
import com.espertech.esper.event.EventAdapterService;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* Output condition for output rate limiting that handles when-then expressions for controlling output.
*/
public class OutputConditionExpressionFactory implements OutputConditionFactory
{
private final ExprEvaluator whenExpressionNodeEval;
private final VariableReadWritePackage variableReadWritePackage;
private final Set<String> variableNames;
private EventType builtinPropertiesEventType;
public OutputConditionExpressionFactory(ExprNode whenExpressionNode, List<OnTriggerSetAssignment> assignments, final StatementContext statementContext)
throws ExprValidationException
{
this.whenExpressionNodeEval = whenExpressionNode.getExprEvaluator();
// determine if using variables
ExprNodeVariableVisitor variableVisitor = new ExprNodeVariableVisitor();
whenExpressionNode.accept(variableVisitor);
variableNames = variableVisitor.getVariableNames();
// determine if using properties
boolean containsBuiltinProperties = false;
if (containsBuiltinProperties(whenExpressionNode))
{
containsBuiltinProperties = true;
}
else
{
if (assignments != null)
{
for (OnTriggerSetAssignment assignment : assignments)
{
if (containsBuiltinProperties(assignment.getExpression()))
{
containsBuiltinProperties = true;
}
}
}
}
if (containsBuiltinProperties)
{
builtinPropertiesEventType = getBuiltInEventType(statementContext.getEventAdapterService());
}
if (assignments != null)
{
variableReadWritePackage = new VariableReadWritePackage(assignments, statementContext.getVariableService(), statementContext.getEventAdapterService());
}
else
{
variableReadWritePackage = null;
}
}
public OutputCondition make(AgentInstanceContext agentInstanceContext, OutputCallback outputCallback) {
return new OutputConditionExpression(outputCallback, agentInstanceContext, this);
}
public ExprEvaluator getWhenExpressionNodeEval() {
return whenExpressionNodeEval;
}
public VariableReadWritePackage getVariableReadWritePackage() {
return variableReadWritePackage;
}
public EventType getBuiltinPropertiesEventType() {
return builtinPropertiesEventType;
}
public Set<String> getVariableNames() {
return variableNames;
}
/**
* Build the event type for built-in properties.
* @param eventAdapterService event adapters
* @return event type
*/
public static EventType getBuiltInEventType(EventAdapterService eventAdapterService)
{
Map<String, Object> outputLimitProperties = new HashMap<String, Object>();
outputLimitProperties.put("count_insert", Integer.class);
outputLimitProperties.put("count_remove", Integer.class);
outputLimitProperties.put("last_output_timestamp", Long.class);
return eventAdapterService.createAnonymousMapType(OutputConditionExpressionFactory.class.getName(), outputLimitProperties);
}
private boolean containsBuiltinProperties(ExprNode expr)
{
ExprNodeIdentifierVisitor propertyVisitor = new ExprNodeIdentifierVisitor(false);
expr.accept(propertyVisitor);
return !propertyVisitor.getExprProperties().isEmpty();
}
}