can we change the scope of the overridden method in the subclass in java? why?
In Java, when you override a method in a subclass, you cannot change the access modifier of that method to be more restrictive than the method in the superclass. However, you can change it to be less restrictive.
public
, the overriding method in the subclass cannot be protected
or private
. It can only be public
or protected
(or default if the superclass method is also default).protected
, the overriding method can be protected
or public
, but not private
or default (if the superclass method is public).class SuperClass {
public void display() {
System.out.println("Display from SuperClass");
}
}
class SubClass extends SuperClass {
// This is valid: same access level
public void display() {
System.out.println("Display from SubClass");
}
// This is valid: less restrictive
protected void displayProtected() {
System.out.println("Display from SubClass with protected access");
}
// This is NOT valid: more restrictive
// private void display() {
// System.out.println("This will cause a compile-time error");
// }
}
You can change the scope of the overridden method in a subclass, but only to be less restrictive. This is to ensure that the polymorphic behavior of the superclass is preserved and that the subclass can be used in place of the superclass without breaking the contract established by the superclass's method visibility.