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Complex event processing and event series analysis component

There is a newer version: 7.1.0

/**************************************************************************************
 * Copyright (C) 2006-2015 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;


/**
 * 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
     * @param restartable
     */
    public void evaluateFalse(EvalStateNode fromNode, boolean restartable);

    public boolean isFilterChildNonQuitting();
}