CLASS_CONSTRUCTOR would be called automatically whenever the class would be accessed – either by creation of an instance or accessing any component. But seems like it is changed with ABAP 740.
With ABAP release 740, you can use the NEW operator to instantiate the object. Read more to learn about NEW Operator.
Gaining access to the object, when working with ABAP Objects Events, which raised the event would be an added advantage for the event handler method.
ABAP Objects doesn’t support Multiple Inheritance – Inheriting from more than one Super class, but similar functionality can be achieved using the interfaces.