| 1 | package dk.deepthought.sidious.ruleengine; |
| 2 | |
| 3 | import java.util.ArrayList; |
| 4 | import java.util.Collection; |
| 5 | import java.util.List; |
| 6 | |
| 7 | import org.apache.commons.logging.Log; |
| 8 | import org.apache.commons.logging.LogFactory; |
| 9 | |
| 10 | import dk.deepthought.sidious.explanation.Explanation; |
| 11 | import dk.deepthought.sidious.explanation.ExplanationEntry; |
| 12 | import dk.deepthought.sidious.goalhandler.Goal; |
| 13 | import dk.deepthought.sidious.rules.Rule; |
| 14 | import dk.deepthought.sidious.supportsystem.PlanRequester; |
| 15 | import dk.deepthought.sidious.supportsystem.Repository; |
| 16 | import dk.deepthought.sidious.supportsystem.State; |
| 17 | import dk.deepthought.sidious.supportsystem.Step; |
| 18 | import dk.deepthought.sidious.supportsystem.SuperLinkID; |
| 19 | |
| 20 | public class RuleEngineImpl implements RuleEngine { |
| 21 | |
| 22 | /** |
| 23 | * Logger for this class |
| 24 | */ |
| 25 | private static final Log logger = LogFactory.getLog(RuleEngineImpl.class); |
| 26 | |
| 27 | /* |
| 28 | * (non-Javadoc) |
| 29 | * |
| 30 | * @see dk.deepthought.sidious.ruleengine.RuleEngine#evaluate(dk.deepthought.sidious.supportsystem.SuperLinkID, |
| 31 | * dk.deepthought.sidious.supportsystem.State, dk.deepthought.sidious.supportsystem.State) |
| 32 | */ |
| 33 | public double evaluate(SuperLinkID requesterID, State current, State next, |
| 34 | Step step) { |
| 35 | if (requesterID == null || current == null || next == null |
| 36 | || step == null) { |
| 37 | logger.error("evaluate(SuperLinkID requesterID=" + requesterID |
| 38 | + ", State current=" + current + ", State next=" + next |
| 39 | + ") - null not valid input"); |
| 40 | throw new IllegalArgumentException("null not valid input"); |
| 41 | } |
| 42 | PlanRequester requester = Repository.getBlackboard().getRequester( |
| 43 | requesterID); |
| 44 | double evaluation = evaluateRules(requester.getRules(), current, next, |
| 45 | step); |
| 46 | return evaluation; |
| 47 | } |
| 48 | |
| 49 | /** |
| 50 | * This method evaluates each of the input <code>rules</code> according to |
| 51 | * the input states (<code>current</code> and <code>next</code>), and |
| 52 | * returns a combined value. |
| 53 | * |
| 54 | * @param rules |
| 55 | * the input collection of rules |
| 56 | * @param current |
| 57 | * the current state |
| 58 | * @param next |
| 59 | * the next state |
| 60 | * @param step |
| 61 | * the step |
| 62 | * @return a combined evaluation, 0 if rules is empty |
| 63 | */ |
| 64 | double evaluateRules(Collection<Rule> rules, State current, State next, |
| 65 | Step step) { |
| 66 | if (rules == null || current == null || next == null || step == null) { |
| 67 | logger.error("evaluateRules(Collection<Rule> rules=" + rules |
| 68 | + ", State current=" + current + ", State next=" + next |
| 69 | + ") - null not valid input"); |
| 70 | throw new IllegalArgumentException("null not valid input"); |
| 71 | } |
| 72 | double evaluation = 0; |
| 73 | List<ExplanationEntry> explanations; |
| 74 | ExplanationEntry entry; |
| 75 | explanations = new ArrayList<ExplanationEntry>(); |
| 76 | for (Rule rule : rules) { |
| 77 | double desire = rule.desire(current, next, step); |
| 78 | evaluation += desire; |
| 79 | entry = new ExplanationEntry(rule.getExplanation(), desire); |
| 80 | explanations.add(entry); |
| 81 | } |
| 82 | step.setExplanation(new Explanation(explanations)); |
| 83 | if (logger.isDebugEnabled()) { |
| 84 | logger.debug("evaluateRules(Collection<Rule> rules=" + rules |
| 85 | + ", State current=" + current + ", State next=" + next |
| 86 | + ") - combined evaluation=" + evaluation); |
| 87 | } |
| 88 | return evaluation; |
| 89 | } |
| 90 | |
| 91 | /* |
| 92 | * (non-Javadoc) |
| 93 | * |
| 94 | * @see dk.deepthought.sidious.ruleengine.RuleEngine#extractGoals(dk.deepthought.sidious.supportsystem.SuperLinkID) |
| 95 | */ |
| 96 | public Collection<Goal> extractGoals(SuperLinkID requesterID) { |
| 97 | PlanRequester requester = Repository.getBlackboard().getRequester( |
| 98 | requesterID); |
| 99 | if (requester == null) { |
| 100 | logger.error("extractGoals(SuperLinkID requesterID=" + requesterID |
| 101 | + ") - requester does not exist - returning empty list"); |
| 102 | return new ArrayList<Goal>(); |
| 103 | } |
| 104 | Collection<Rule> rules = requester.getRules(); |
| 105 | Collection<Goal> returnCollection = extractGoalsFromRules(rules); |
| 106 | if (logger.isDebugEnabled()) { |
| 107 | logger.debug("extractGoals(SuperLinkID requesterID=" + requesterID |
| 108 | + ") - returned goals=" + returnCollection); |
| 109 | } |
| 110 | return returnCollection; |
| 111 | } |
| 112 | |
| 113 | /** |
| 114 | * Method extracts and returns all goals from the input <code>rules</code>. |
| 115 | * |
| 116 | * @param rules |
| 117 | * the rules the goals will be extracted from |
| 118 | * @return the extracted goals |
| 119 | */ |
| 120 | Collection<Goal> extractGoalsFromRules(Collection<Rule> rules) { |
| 121 | if (rules == null) { |
| 122 | logger |
| 123 | .error("extractGoalsFromRules(Collection<Rule> rules=null) - null not valid"); |
| 124 | throw new IllegalArgumentException("Null not valid"); |
| 125 | } |
| 126 | Collection<Goal> goals = new ArrayList<Goal>(); |
| 127 | for (Rule rule : rules) { |
| 128 | goals.addAll(rule.getGoals()); |
| 129 | } |
| 130 | if (logger.isDebugEnabled()) { |
| 131 | logger.debug("extractGoalsFromRules(Collection<Rule> rules=" |
| 132 | + rules + ") - return value=" + goals); |
| 133 | } |
| 134 | return goals; |
| 135 | } |
| 136 | |
| 137 | } |