/**************************************************************************************
* 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.pattern;
/**
* Interface for nodes in an expression evaluation state tree that are being informed by a child that the
* event expression fragments (subtrees) which the child represents has turned true (evaluateTrue method)
* or false (evaluateFalse).
*/
public interface Evaluator
{
/**
* Indicate a change in truth value to true.
* @param matchEvent is the container for events that caused the change in truth value
* @param fromNode is the node that indicates the change
* @param isQuitted is an indication of whether the node continues listenening or stops listening
*/
public void evaluateTrue(MatchedEventMap matchEvent, EvalStateNode fromNode, boolean isQuitted);
/**
* Indicate a change in truth value to false.
* @param fromNode is the node that indicates the change
*/
public void evaluateFalse(EvalStateNode fromNode);
public boolean isFilterChildNonQuitting();
}