when to use abstract class and when to use interface?
Answer Posted / praveen reddy.e
generally abstract class is written when there are some common features shared by all the objects as they are.
for eg take a class Wholesaler which represents a whole sale shop with text books and stationary like pens,note books etc
class wholesaler
{
void text_books()
{
//text books of X class
}
void stationary();//this can be pens,papers or note books
}
Let us take a Retailer1,a class which represents a retail shop.Retailer1 wants text books of X class and some pens.similarly,Retailer2 also wants text books of X class and some papers.In this case we can understand that the void text_books() is the common feature shared by both the Retailers.But the stationary asked by the Retailers is different.This means ,The stationary has different implementations for different retailers but there is a common feature,i.e,the text books.So in this case,the programer design the Wholesaler class as abstract class.Retailer1 ane Retailer2 as sub classes.
On the other hand, the programer uses an interface if all the features need to be implemented differently for different objects.Suppose,Retailer1 asks for VII class text books and Retailer2 asks for X class books,then even the text_books() of Wholesaler class needs different implementations depending upon the retailer.It means ,the void text_books() and also void stationary() method should be implemented differently depending upon the retailer.So in this case the programer desings the Wholesaler as an interface and Retailer1 and Retailer2 become implementaion classes
| Is This Answer Correct ? | 4 Yes | 0 No |
Post New Answer View All Answers
Explain some best practices you would apply while using collection in java?
Can we write method inside a method in java?
How can we find the actual size of an object on the heap?
Can java inner class be static?
Can we overload the main() method?
Can main() method in java can return any data?
What is the purpose of a volatile variable?
Why scanner is used in java?
What is the base class of all exception classes in java?
What is object cloning in Java?
What are register variables what are the advantages?
What is a priority queue java?
can I implement my own start() method? : Java thread
Can arraylist hold different types java?
What is command line argument