Why there is abstract class in Java?

Abstract classes provide a simple and easy way to version our components . … If we want to provide common, implemented functionality among all implementations of our component, use an abstract class. Abstract classes allow us to partially implement our class, whereas interfaces contain no implementation for any members.

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Is abstract class necessary in Java?

It’s not necessary for an abstract class to have abstract method . We can mark a class as abstract even if it doesn’t declare any abstract methods. If abstract class doesn’t have any method implementation, its better to use interface because java doesn’t support multiple class inheritance.

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