Рассмотрим следующие классы кода.
public class A
{
public A()
{
callCreation();
}
protected void callCreation()
{
System.out.println("A Created!!");
}
}
public class B extends A
{
protected void callCreation()
{
System.out.println("B Created!!");
}
}
public class C extends B
{
protected void callCreation()
{
System.out.println("C Created!!");
}
public static void main(String[] args)
{
A a = new A();
A b = new B();
A c = new C();
}
}
Результат запуска класса C приведен ниже.
A Created!! B Created!! C Created!!
The first output line in the output
A Created!!is printed because when the constructor of class A is called, it calls the super class's constructor (java.lang.Object) implicitly before calling the callCreation() method in the class A's constructor. And this will be the case for B and C classes too. In that case when the constructor of B is called the call flow should be typically : B's constructor -> A's Constructor -> java.lang.Object's Constructor -> come back to A's callCreation() method to finish calling A's constructor. If so how is the overridden value printed and not the super class's value is printed? So the question is 'when is an object of a class created exactly? to put it in other words, the object of a class should be created only after the constructor finishes calling/initializing all the elements within itself. If so how can a method be called from a child class and not from the parent class?