001 /**
002 * Copyright 2005-2013 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 */
016 package org.kuali.rice.kew.rule;
017
018 import org.apache.log4j.Logger;
019 import org.kuali.rice.kew.api.exception.WorkflowException;
020 import org.kuali.rice.kew.engine.RouteContext;
021
022 import javax.script.ScriptEngine;
023 import javax.script.ScriptException;
024 import java.util.ArrayList;
025 import java.util.List;
026
027 /**
028 * An extension of BSFRuleExpression that makes it easier to accumulate a list of responsibilities
029 * to emit.
030 *
031 * @author Kuali Rice Team (rice.collab@kuali.org)
032 */
033 public class AccumulatingBSFRuleExpression extends BSFRuleExpression {
034 private static final Logger LOG = Logger.getLogger(AccumulatingBSFRuleExpression.class);
035
036 @Override
037 protected void declareBeans(ScriptEngine engine, Rule rule, RouteContext context) throws ScriptException {
038 // define the standard beans
039 super.declareBeans(engine, rule, context);
040 // define our special rule helper class
041 RuleHelper rh = new RuleHelper(rule, context);
042 engine.put("metarule", rh); // backwards compatibility with existing KRAMetaRuleExpression usage
043 engine.put("rulehelper", rh);
044 }
045
046 /**
047 * Helper class that is exposed to groovy scripts
048 */
049 private static final class RuleHelper {
050 private Rule rule;
051 private WorkflowRuleAPI workflow;
052 /**
053 * Responsibilities accumulated during the evaluation
054 */
055 private List<org.kuali.rice.kew.api.rule.RuleResponsibility> responsibilities = new ArrayList<org.kuali.rice.kew.api.rule.RuleResponsibility>();
056 private int responsibilityPriority = 0;
057
058 private RuleHelper(Rule rule, RouteContext context) {
059 this.workflow = new WorkflowRuleAPI(context);
060 this.rule = rule;
061 }
062
063 /**
064 * @return the accumulated responsibilities
065 */
066 public List<org.kuali.rice.kew.api.rule.RuleResponsibility> getResponsibilities() {
067 return responsibilities;
068 }
069
070 /**
071 * @param success whether the result should be successful
072 * @return the RuleExpressionResult with success flag and accumulated responsibilities
073 */
074 public RuleExpressionResult getResult(boolean success) {
075 return new RuleExpressionResult(rule, success, responsibilities);
076 }
077
078 /**
079 * Adds the responsibilities in the result to the list of accumulated responsibilities
080 * @param result a RuleExpressionResult whose responsibilities to accumulate
081 */
082 public void accumulate(RuleExpressionResult result) {
083 if (result.getResponsibilities() == null || result.getResponsibilities().size() == 0) return;
084
085 Integer curPriority = Integer.valueOf(responsibilityPriority);
086 for (org.kuali.rice.kew.api.rule.RuleResponsibility responsibility: result.getResponsibilities()) {
087 org.kuali.rice.kew.api.rule.RuleResponsibility.Builder builder =
088 org.kuali.rice.kew.api.rule.RuleResponsibility.Builder.create(responsibility);
089 builder.setPriority(curPriority);
090 responsibilities.add(builder.build());
091 }
092 // increment responsibilityPriority for next rule expression result responsibilities
093 responsibilityPriority++;
094 }
095
096 /**
097 * Evaluates a named rule accumulating responsibilities regardless of rule success
098 * @param ruleName the name of the rule to evaluate
099 * @return whether the rule was successful
100 */
101 public boolean evalRule(String ruleName) throws WorkflowException {
102 RuleExpressionResult result = workflow.invokeRule(ruleName);
103 accumulate(result);
104 return result.isSuccess();
105 }
106
107 /**
108 * Evaluates a named rule and if it is successful accumulates the rule responsibilities
109 * @param ruleName the name of the rule to evaluate
110 * @param accumOnSuccess whether to accumulate the rules responsibilities on success (true), or on failure (false)
111 * @return whether the rule was successful
112 */
113 public boolean evalRule(String ruleName, boolean accumOnSuccess) throws WorkflowException {
114 RuleExpressionResult result = workflow.invokeRule(ruleName);
115 if (accumOnSuccess == result.isSuccess()) {
116 accumulate(result);
117 }
118 return result.isSuccess();
119 }
120
121 }
122 }