Fix validation issue for non annotated fact parameters

Resolves #165

easy-rules-core/src/main/java/org/jeasy/rules/core/RuleDefinitionValidator.java

@@ -70,7 +70,7 @@ private void checkConditionMethod(final Object rule) {
         Method conditionMethod = conditionMethods.get(0);
 
         if (!isConditionMethodWellDefined(conditionMethod)) {
-            throw new IllegalArgumentException(format("Condition method '%s' defined in rule '%s' must be public, may have parameters annotated with @Fact (and/or exactly one parameter of type or extending Facts) and return boolean type.", conditionMethod, rule.getClass().getName()));
+            throw new IllegalArgumentException(format("Condition method '%s' defined in rule '%s' must be public, must return boolean type and may have parameters annotated with @Fact (and/or exactly one parameter of type Facts or one of its sub-types).", conditionMethod, rule.getClass().getName()));
         }
     }
 
@@ -82,7 +82,7 @@ private void checkActionMethods(final Object rule) {
 
         for (Method actionMethod : actionMethods) {
             if (!isActionMethodWellDefined(actionMethod)) {
-                throw new IllegalArgumentException(format("Action method '%s' defined in rule '%s' must be public, must return void type and may have parameters annotated with @Fact (and/or exactly one parameter of type or extending Facts).", actionMethod, rule.getClass().getName()));
+                throw new IllegalArgumentException(format("Action method '%s' defined in rule '%s' must be public, must return void type and may have parameters annotated with @Fact (and/or exactly one parameter of type Facts or one of its sub-types).", actionMethod, rule.getClass().getName()));
             }
         }
     }
@@ -134,13 +134,26 @@ private boolean validParameters(final Method method) {
         if(notAnnotatedParameterCount > 1){
             return false;
         }
-        Class<?>[] parameterTypes = method.getParameterTypes();
-        if(parameterTypes.length == 1 && notAnnotatedParameterCount == 1){
-            return Facts.class.isAssignableFrom(parameterTypes[0]);
+        if (notAnnotatedParameterCount == 1) {
+            Class<?>[] parameterTypes = method.getParameterTypes();
+            int index = getIndexOfParameterOfTypeFacts(method); // TODO use method.getParameters when moving to Java 8
+            return Facts.class.isAssignableFrom(parameterTypes[index]);
         }
         return true;
     }
 
+    private int getIndexOfParameterOfTypeFacts(Method method) {
+        Class<?>[] parameterTypes = method.getParameterTypes();
+        int index = 0;
+        for (Class<?> parameterType : parameterTypes) {
+            if (Facts.class.isAssignableFrom(parameterType)) {
+                return index;
+            }
+            index++;
+        }
+        return 0;
+    }
+
     private boolean isActionMethodWellDefined(final Method method) {
         return Modifier.isPublic(method.getModifiers())
                 && method.getReturnType().equals(Void.TYPE)

easy-rules-core/src/test/java/org/jeasy/rules/annotation/AnnotatedRuleWithOneParameterNotAnnotatedWithFactAndNotOfTypeFacts.java

@@ -0,0 +1,38 @@
+/**
+ * The MIT License
+ *
+ *  Copyright (c) 2019, Mahmoud Ben Hassine ([email protected])
+ *
+ *  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.jeasy.rules.annotation;
+
+@Rule
+public class AnnotatedRuleWithOneParameterNotAnnotatedWithFactAndNotOfTypeFacts {
+
+    @Condition
+    public boolean when(@Fact("fact1") Object fact1, Object fact2) {
+        return true;
+    }
+
+    @Action
+    public void then(@Fact("fact1") Object fact1, Object fact2) {
+    }
+
+}

easy-rules-core/src/test/java/org/jeasy/rules/core/RuleDefinitionValidatorTest.java

@@ -74,6 +74,11 @@ public void conditionMethodMustReturnBooleanType() {
         ruleDefinitionValidator.validateRuleDefinition(new AnnotatedRuleWithConditionMethodHavingNonBooleanReturnType());
     }
 
+    @Test(expected = IllegalArgumentException.class)
+    public void conditionMethodParametersShouldAllBeAnnotatedWithFactUnlessExactlyOneOfThemIsOfTypeFacts() {
+        ruleDefinitionValidator.validateRuleDefinition(new AnnotatedRuleWithOneParameterNotAnnotatedWithFactAndNotOfTypeFacts());
+    }
+
     /*
      * Action method tests
      */
@@ -102,6 +107,11 @@ public void actionMethodMustReturnVoid() {
         ruleDefinitionValidator.validateRuleDefinition(new AnnotatedRuleWithActionMethodThatReturnsNonVoidType());
     }
 
+    @Test(expected = IllegalArgumentException.class)
+    public void actionMethodParametersShouldAllBeAnnotatedWithFactUnlessExactlyOneOfThemIsOfTypeFacts() {
+        ruleDefinitionValidator.validateRuleDefinition(new AnnotatedRuleWithOneParameterNotAnnotatedWithFactAndNotOfTypeFacts());
+    }
+
     /*
      * Priority method tests
      */