issue #37 : add Facts abstraction and update APIs accordingly

easyrules-core/src/main/java/org/easyrules/api/Facts.java

@@ -0,0 +1,61 @@
+/**
+ * The MIT License
+ *
+ *  Copyright (c) 2017, Mahmoud Ben Hassine (mahmoud.benhassine@icloud.com)
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in
+ *  all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ *  THE SOFTWARE.
+ */
+package org.easyrules.api;
+
+import java.util.*;
+
+import static java.lang.String.format;
+
+public class Facts implements Iterable<Map.Entry<String, Object>> {
+
+    private Map<String, Object> facts = new HashMap<>();
+
+    public void add(String name, Object fact) {
+        facts.put(name, fact);
+    }
+
+    public void remove(String name) {
+        facts.remove(name);
+    }
+
+    public Object get(String name) {
+        return facts.get(name);
+    }
+
+    @Override
+    public Iterator<Map.Entry<String, Object>> iterator() {
+        return facts.entrySet().iterator();
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder stringBuilder = new StringBuilder("Facts {").append("\n");
+        for (Map.Entry<String, Object> fact : facts.entrySet()) {
+            stringBuilder.append(format("   Fact { %s : %s }", fact.getKey(), fact.getValue().toString()));
+            stringBuilder.append("\n");
+        }
+        stringBuilder.append("}");
+        return  stringBuilder.toString();
+    }
+}

easyrules-core/src/main/java/org/easyrules/api/Rule.java

@@ -30,7 +30,7 @@ package org.easyrules.api;
  *
  * @author Mahmoud Ben Hassine (mahmoud.benhassine@icloud.com)
  */
-public interface Rule {
+public interface Rule extends Comparable<Rule> {
 
     /**
      * Default rule name.
@@ -67,14 +67,14 @@ public interface Rule {
 
     /**
      * Rule conditions abstraction : this method encapsulates the rule's conditions.
-     * @return true if the rule should be applied, false else
+     * @return true if the rule should be applied given the provided facts, false else
      */
-    boolean evaluate();
+    boolean evaluate(Facts facts);
 
     /**
      * Rule actions abstraction : this method encapsulates the rule's actions.
      * @throws Exception thrown if an exception occurs during actions performing
      */
-    void execute() throws Exception;
+    void execute(Facts facts) throws Exception;
 
 }

easyrules-core/src/main/java/org/easyrules/api/RuleListener.java

@@ -34,9 +34,10 @@ public interface RuleListener {
      * Triggered before the evaluation of a rule.
      *
      * @param rule being evaluated
+     * @param facts known before evaluating the rule
      * @return true if the rule should be evaluated, false otherwise
      */
-    boolean beforeEvaluate(Rule rule);
+    boolean beforeEvaluate(Rule rule, Facts facts);
 
     /**
      * Triggered after the evaluation of a rule.
@@ -50,22 +51,25 @@ public interface RuleListener {
      * Triggered before the execution of a rule.
      *
      * @param rule the current rule
+     * @param rule known before executing the rule
      */
-    void beforeExecute(Rule rule);
+    void beforeExecute(Rule rule, Facts facts);
 
     /**
      * Triggered after a rule has been executed successfully.
      *
      * @param rule the current rule
+     * @param facts known after executing the rule
      */
-    void onSuccess(Rule rule);
+    void onSuccess(Rule rule, Facts facts);
 
     /**
      * Triggered after a rule has failed.
      *
      * @param rule      the current rule
      * @param exception the exception thrown when attempting to execute the rule
+     * @param facts known after executing the rule
      */
-    void onFailure(Rule rule, Exception exception);
+    void onFailure(Rule rule, Exception exception, Facts facts);
 
 }

easyrules-core/src/main/java/org/easyrules/api/Rules.java

@@ -0,0 +1,75 @@
+/**
+ * The MIT License
+ *
+ *  Copyright (c) 2017, Mahmoud Ben Hassine (mahmoud.benhassine@icloud.com)
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in
+ *  all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ *  THE SOFTWARE.
+ */
+package org.easyrules.api;
+
+import org.easyrules.core.RuleProxy;
+
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.Set;
+import java.util.TreeSet;
+
+public class Rules implements Iterable<Rule> {
+
+    private Set<Rule> rules = new TreeSet<>();
+
+    public Rules(Set<Rule> rules) {
+        this.rules = rules;
+    }
+
+    public Rules(Rule... rules ) {
+        Collections.addAll(this.rules, rules);
+    }
+
+    public Rules(Object... rules ) {
+        for (Object rule : rules) {
+            this.register(RuleProxy.asRule(rule));
+        }
+    }
+
+    public void register(Object rule) {
+        rules.add(RuleProxy.asRule(rule));
+    }
+
+    public void unregister(Object rule) {
+        rules.remove(RuleProxy.asRule(rule));
+    }
+
+    public boolean isEmpty() {
+        return rules.isEmpty();
+    }
+
+    public void clear() {
+        rules.clear();
+    }
+
+    @Override
+    public Iterator<Rule> iterator() {
+        return rules.iterator();
+    }
+
+    public void sort() {
+        rules = new TreeSet<>(rules);
+    }
+}

easyrules-core/src/main/java/org/easyrules/api/RulesEngine.java

@@ -52,34 +52,6 @@ public interface RulesEngine {
      */
     RulesEngineParameters getParameters();
 
-    /**
-     * Register a rule in the rules engine registry.
-     *
-     * @param rule the rule to register
-     */
-    void registerRule(Object rule);
-
-    /**
-     * Unregister a rule from the rules engine registry.
-     *
-     * @param rule the rule to unregister
-     */
-    void unregisterRule(Object rule);
-
-    /**
-     * Unregister a rule by name from the rules engine registry.
-     *
-     * @param ruleName the name of the rule to unregister
-     */
-    void unregisterRule(String ruleName);
-
-    /**
-     * Return the set of registered rules.
-     *
-     * @return the set of registered rules
-     */
-    Set<Rule> getRules();
-
     /**
      * Return the list of registered rule listeners.
      *
@@ -88,18 +60,13 @@ public interface RulesEngine {
     List<RuleListener> getRuleListeners();
 
     /**
-     * Fire all registered rules.
+     * Fire all registered rules on given facts.
      */
-    void fireRules();
+    void fire(Rules rules, Facts facts);
 
     /**
      * Check rules without firing them.
      * @return a map with the result of evaluation of each rule
      */
-    Map<Rule, Boolean> checkRules();
-
-    /**
-     * Clear rules engine registry.
-     */
-    void clearRules();
+    Map<Rule, Boolean> check(Rules rules, Facts facts);
 }