What are abstract classes in Java?

Abstract class in Java

Abstract class: is a restricted class that cannot be used to create objects (to access it, it must be inherited from another class). Abstract method: can only be used in an abstract class, and it does not have a body. The body is provided by the subclass (inherited from).

An abstract class may have static fields and static methods. You can use these static members with a class reference (for example, AbstractClass.

Abstract classes can have instance variables (these are inherited by child classes). Interfaces can’t. Finally, a concrete class can only extend one class (abstract or otherwise).