001/**
002 * Copyright 2005-2015 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.rice.krms.api.engine;
017
018/**
019 * Defines various possible flags that can be used to control how the rules
020 * engine executes and performs it's evaluation of rules.  These flags are
021 * meant to be set to either true or false.  This is done using the
022 * {@link ExecutionOptions} that are passed to the engine at execution time.
023 * 
024 * @see ExecutionOptions
025 * 
026 * @author Kuali Rice Team (rice.collab@kuali.org)
027 *
028 */
029public enum ExecutionFlag {
030
031        /**
032         * Indicates that the engine should perform default logging by recording
033         * each {@link ResultEvent} in the {@link EngineResults}.  Default value
034         * is false.
035         * 
036         * @see EngineResults
037         */
038        LOG_EXECUTION(false),
039        
040        /**
041         * Indicates that the selection criteria which is passed to the engine
042         * at the time of execution must be able to select a valid context in
043         * order for engine execution to proceed.  Default value is false,
044         * when false the engine will simply not execute if no valid context
045         * can be located for the specified selection criteria.
046         * 
047         * @see SelectionCriteria
048         */
049        CONTEXT_MUST_EXIST(false),
050        
051        /**
052         * Instructs the engine to evaluate all propositions.  If this value is
053         * set to false, the engine may skip (aka short circuit) propositions that 
054         * do not influence the overall outcome of the proposition tree.  
055         */
056        EVALUATE_ALL_PROPOSITIONS(false);
057        
058        private final boolean defaultValue;
059
060    /**
061     * Create an ExecutionFlag with the given value
062     * @param defaultValue to set the defaultValue to
063     */
064        private ExecutionFlag(boolean defaultValue) {
065                this.defaultValue = defaultValue;
066        }
067        
068        /**
069         * Returns the default value for the flag if it has not been explicitly set.
070         * 
071         * @return the default value for the flag
072         */
073        public boolean getDefaultValue() {
074                return this.defaultValue;
075        }
076        
077}