Extending a class in Scala user can design an inherited class. To extend a class in Scala we use extends keyword. there are two restrictions to extend a class in Scala :
- To override method in scala override keyword is required.
- Only the primary constructor can pass parameters to the base constructor.
Syntax:
class derived_class_name extends base_class_name
{
// Methods and fields
}
Example:
Output:
Author name: chaitanyashah
Total numbers of articles: 30
In the above example
Geeks1 is the
base class and
Geeks2 is the
derived class which is derived from Geeks1 using extends keyword. In the main method when we create the object of Geeks2 class, a copy of all the methods and fields of the base class acquires memory in this object. That is why by using the object of the derived class we can also access the members of the base class.
Example:
Output:
Name: geek1
Age: 32
Name: geek2
Height: 164
In the above example
Parent is the
base class Child1 and
Child2 are the
derived class which is derived from Parent using extends keyword. In the main method when we create the objects of Child1 and Child2 class a copy of all the methods and fields of the base class acquires memory in this object.
Example:
Output:
new startHeight : 25
new speed value: 25
new gear value: 5
In above program, when an object of MountainBike class is created, a copy of the all methods and fields of the superclass acquire memory in this object.
