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 java.util.ArrayList;
19 import java.util.List;
20
21 import org.apache.bsf.BSFException;
22 import org.apache.bsf.BSFManager;
23 import org.apache.log4j.Logger;
24 import org.kuali.rice.kew.engine.RouteContext;
25 import org.kuali.rice.kew.exception.WorkflowException;
26
27
28 /**
29 * An extension of BSFRuleExpression that makes it easier to accumulate a list of responsibilities
30 * to emit.
31 *
32 * @author Kuali Rice Team (rice.collab@kuali.org)
33 */
34 public class AccumulatingBSFRuleExpression extends BSFRuleExpression {
35 private static final Logger LOG = Logger.getLogger(AccumulatingBSFRuleExpression.class);
36
37 @Override
38 protected void declareBeans(BSFManager manager, Rule rule, RouteContext context) throws BSFException {
39 // define the standard beans
40 super.declareBeans(manager, rule, context);
41 // define our special rule helper class
42 RuleHelper rh = new RuleHelper(rule, context);
43 manager.declareBean("metarule", rh, RuleHelper.class); // backwards compatibility with existing KRAMetaRuleExpression usage
44 manager.declareBean("rulehelper", rh, RuleHelper.class);
45 }
46
47 /**
48 * Helper class that is exposed to groovy scripts
49 */
50 private static final class RuleHelper {
51 private Rule rule;
52 private WorkflowRuleAPI workflow;
53 /**
54 * Responsibilities accumulated during the evaluation
55 */
56 private List<RuleResponsibility> responsibilities = new ArrayList<RuleResponsibility>();
57 private int responsibilityPriority = 0;
58
59 private RuleHelper(Rule rule, RouteContext context) {
60 this.workflow = new WorkflowRuleAPI(context);
61 this.rule = rule;
62 }
63
64 /**
65 * @return the accumulated responsibilities
66 */
67 public List<RuleResponsibility> getResponsibilities() {
68 return responsibilities;
69 }
70
71 /**
72 * @param success whether the result should be successful
73 * @return the RuleExpressionResult with success flag and accumulated responsibilities
74 */
75 public RuleExpressionResult getResult(boolean success) {
76 return new RuleExpressionResult(rule, success, responsibilities);
77 }
78
79 /**
80 * Adds the responsibilities in the result to the list of accumulated responsibilities
81 * @param result a RuleExpressionResult whose responsibilities to accumulate
82 */
83 public void accumulate(RuleExpressionResult result) {
84 if (result.getResponsibilities() == null || result.getResponsibilities().size() == 0) return;
85
86 Integer curPriority = Integer.valueOf(responsibilityPriority);
87 for (RuleResponsibility responsibility: result.getResponsibilities()) {
88 responsibility.setPriority(curPriority);
89 responsibilities.add(responsibility);
90 }
91 // increment responsibilityPriority for next rule expression result responsibilities
92 responsibilityPriority++;
93 }
94
95 /**
96 * Evaluates a named rule accumulating responsibilities regardless of rule success
97 * @param ruleName the name of the rule to evaluate
98 * @return whether the rule was successful
99 */
100 public boolean evalRule(String ruleName) throws WorkflowException {
101 RuleExpressionResult result = workflow.invokeRule(ruleName);
102 accumulate(result);
103 return result.isSuccess();
104 }
105
106 /**
107 * Evaluates a named rule and if it is successful accumulates the rule responsibilities
108 * @param ruleName the name of the rule to evaluate
109 * @param accumOnSuccess whether to accumulate the rules responsibilities on success (true), or on failure (false)
110 * @return whether the rule was successful
111 */
112 public boolean evalRule(String ruleName, boolean accumOnSuccess) throws WorkflowException {
113 RuleExpressionResult result = workflow.invokeRule(ruleName);
114 if (accumOnSuccess == result.isSuccess()) {
115 accumulate(result);
116 }
117 return result.isSuccess();
118 }
119
120 }
121 }