1 /*
2 * Copyright 2007-2008 The Kuali Foundation
3 *
4 * Licensed under the Educational Community License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.opensource.org/licenses/ecl2.php
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package org.kuali.rice.kew.rule;
17
18 import org.apache.log4j.Logger;
19 import org.kuali.rice.kew.engine.RouteContext;
20 import org.kuali.rice.kew.exception.WorkflowException;
21
22 import javax.script.ScriptEngine;
23 import javax.script.ScriptException;
24 import java.util.ArrayList;
25 import java.util.List;
26
27 /**
28 * An extension of BSFRuleExpression that makes it easier to accumulate a list of responsibilities
29 * to emit.
30 *
31 * @author Kuali Rice Team (rice.collab@kuali.org)
32 */
33 public class AccumulatingBSFRuleExpression extends BSFRuleExpression {
34 private static final Logger LOG = Logger.getLogger(AccumulatingBSFRuleExpression.class);
35
36 @Override
37 protected void declareBeans(ScriptEngine engine, Rule rule, RouteContext context) throws ScriptException {
38 // define the standard beans
39 super.declareBeans(engine, rule, context);
40 // define our special rule helper class
41 RuleHelper rh = new RuleHelper(rule, context);
42 engine.put("metarule", rh); // backwards compatibility with existing KRAMetaRuleExpression usage
43 engine.put("rulehelper", rh);
44 }
45
46 /**
47 * Helper class that is exposed to groovy scripts
48 */
49 private static final class RuleHelper {
50 private Rule rule;
51 private WorkflowRuleAPI workflow;
52 /**
53 * Responsibilities accumulated during the evaluation
54 */
55 private List<RuleResponsibility> responsibilities = new ArrayList<RuleResponsibility>();
56 private int responsibilityPriority = 0;
57
58 private RuleHelper(Rule rule, RouteContext context) {
59 this.workflow = new WorkflowRuleAPI(context);
60 this.rule = rule;
61 }
62
63 /**
64 * @return the accumulated responsibilities
65 */
66 public List<RuleResponsibility> getResponsibilities() {
67 return responsibilities;
68 }
69
70 /**
71 * @param success whether the result should be successful
72 * @return the RuleExpressionResult with success flag and accumulated responsibilities
73 */
74 public RuleExpressionResult getResult(boolean success) {
75 return new RuleExpressionResult(rule, success, responsibilities);
76 }
77
78 /**
79 * Adds the responsibilities in the result to the list of accumulated responsibilities
80 * @param result a RuleExpressionResult whose responsibilities to accumulate
81 */
82 public void accumulate(RuleExpressionResult result) {
83 if (result.getResponsibilities() == null || result.getResponsibilities().size() == 0) return;
84
85 Integer curPriority = Integer.valueOf(responsibilityPriority);
86 for (RuleResponsibility responsibility: result.getResponsibilities()) {
87 responsibility.setPriority(curPriority);
88 responsibilities.add(responsibility);
89 }
90 // increment responsibilityPriority for next rule expression result responsibilities
91 responsibilityPriority++;
92 }
93
94 /**
95 * Evaluates a named rule accumulating responsibilities regardless of rule success
96 * @param ruleName the name of the rule to evaluate
97 * @return whether the rule was successful
98 */
99 public boolean evalRule(String ruleName) throws WorkflowException {
100 RuleExpressionResult result = workflow.invokeRule(ruleName);
101 accumulate(result);
102 return result.isSuccess();
103 }
104
105 /**
106 * Evaluates a named rule and if it is successful accumulates the rule responsibilities
107 * @param ruleName the name of the rule to evaluate
108 * @param accumOnSuccess whether to accumulate the rules responsibilities on success (true), or on failure (false)
109 * @return whether the rule was successful
110 */
111 public boolean evalRule(String ruleName, boolean accumOnSuccess) throws WorkflowException {
112 RuleExpressionResult result = workflow.invokeRule(ruleName);
113 if (accumOnSuccess == result.isSuccess()) {
114 accumulate(result);
115 }
116 return result.isSuccess();
117 }
118
119 }
120 }