BAEL-2726_Introduction_to_Traits_in_Groovy (#6384)

core-groovy/src/main/groovy/com/baeldung/traits/Car.groovy

@@ -0,0 +1,3 @@
+package com.baeldung
+
+class Car implements VehicleTrait {}

core-groovy/src/main/groovy/com/baeldung/traits/UserTrait.groovy

@@ -22,7 +22,7 @@ trait UserTrait implements Human {
         msg
     }
     
-    def whoAmI() {
+    def self() {
         return this 
     }
     

core-groovy/src/main/groovy/com/baeldung/traits/VehicleTrait.groovy

@@ -0,0 +1,9 @@
+package com.baeldung
+
+trait VehicleTrait extends WheelTrait {
+    
+    String showWheels() {
+        return "Num of Wheels $noOfWheels" 
+    }
+    
+}

core-groovy/src/main/groovy/com/baeldung/traits/WheelTrait.groovy

@@ -0,0 +1,7 @@
+package com.baeldung
+
+trait WheelTrait {
+    
+    int noOfWheels
+    
+}

core-groovy/src/test/groovy/com/baeldung/traits/TraitsUnitTest.groovy

@@ -57,7 +57,7 @@ class TraitsUnitTest extends Specification {
     
     def 'Should return employee instance when using Employee.whoAmI method' () {
         when:
-            def emp = employee.whoAmI()
+            def emp = employee.self()
         then:
             emp
             emp instanceof Employee