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Why the instance variable of the super class is not overridden in the sub class?
Because instance variables CANNOT be overridden in Java. In Java, only methods can be overridden. When you declare a field with the same name as an existing field in a superclass, the new field hides the existing field. The existing field from the superclass is still present in the subclass, and can even be used …
Do instance variables get inherited?
Inheritance and Constructors. Subclasses inherit public methods from the superclass that they extend, but they cannot access the private instance variables of the superclass directly and must use the public accessor and mutator methods. And subclasses do not inherit constructors from the superclass.
What do instance variables do?
Instance variables hold values that must be referenced by more than one method, constructor or block, or essential parts of an object’s state that must be present throughout the class. Instance variables can be declared at the class level before or after use. Access modifiers can be given for instance variables.
Why is the instance variable of the Super class is not?
Imagine if Java allows variable overriding and we change the type of a variable from int to Object in the Child class. It will break any method using that variable, and because the child has inherited those methods from the Parent, the compiler will give errors in the Child class.
When to use Super reference variable in Java?
Whenever you create the instance of subclass, an instance of parent class is created implicitly which is referred by super reference variable. super can be used to refer immediate parent class instance variable. super can be used to invoke immediate parent class method.
Is it possible to override an instance variable in Java?
If you have the need to override an instance variable, you are almost certainly inheriting from the worng class. In some languages you can hide the instance variable by supplying a new one: The methods of class A can still access the original V1.
When to declare an instance variable in Java?
Instance variables can be declared at the class level before or after use. Access modifiers can be given for instance variables. The instance variables are visible for all methods, constructors, and block in the class.