code: private static boolean areEquals(Object obj1, Object obj2){
          return obj1 != null ? obj1.equals(obj2) : obj2 == null;
      }
docs: Convenient method that return <code>true</code> if both parameter are equals.
  It supports null value.
  
  @param obj1 The first object to check for equality
  @param obj2 The second object to check for equality
  @return <code>true</code> if both object are areEquals or null, <code>false</code> otherwise.