Inheritance in Java – creating an object of the subclass invokes also the constructor of the superclass. Why exactly?

by

It doesn’t create two objects, only one: B.

When inheriting from another class, you must call super() in your constructor. If you don’t, the compiler will insert that call for you as you can plainly see.

The superclass constructors are called because otherwise the object would be left in an uninitialized state, possibly unbeknownst to the developer of the subclass.

Your subclass actually looks like this after the compiler inserts the super call:

public class B extends A {
    public B() {
        super();
        System.out.println("Bye!");
    }
}

More Related Contents:

  1. Why i can’t initialize variable in parent class’ constructor? [closed]
  2. Implicit super constructor Event() is undefined [duplicate]
  3. What’s wrong with overridable method calls in constructors?
  4. Java Constructor Inheritance
  5. In what order do static blocks and initialization blocks execute when using inheritance?
  6. Is it possible to call subclasses’ methods on a superclass object?
  7. When do you need to explicitly call a superclass constructor?
  8. State of Derived class object when Base class constructor calls overridden method in Java
  9. Private members in Java inheritance
  10. Access subclass fields from a base class in Java
  11. Why are constructors not inherited in java?
  12. order of constructor calls in multilevel inheritance in java [duplicate]
  13. how to inherit Constructor from super class to sub class
  14. Does an instance of superclass get created when we instantiate an object?
  15. Initialize field before super constructor runs?
  16. Type mismatch: cannot convert from double to double[]
  17. Why do this() and super() have to be the first statement in a constructor?
  18. How to determine an object’s class?
  19. What is an interface in Java?
  20. Why is it not possible to extend annotations in Java?
  21. Why to use Interfaces, Multiple Inheritance vs Interfaces, Benefits of Interfaces?
  22. What is the point of setters and getters in java? [duplicate]
  23. When do I use super()?
  24. Calling super super class method
  25. extends of the class with private constructor
  26. Java method overriding and variable shadowing
  27. Java: accessing private constructor with type parameters
  28. When do instance variables get initialized and values assigned?
  29. Java N-Dimensional Arrays
  30. Java. Implicit super constructor Employee() is undefined. Must explicitly invoke another constructor [duplicate]

Leave a Comment