Explain the difference between interfaces and abstract classes in Java.

Question

Why do we need interfaces if there are abstract classes?

Accepted Answer

Interfaces are preferred when you want to provide a contract for multiple classes to fulfill, while abstract classes are preferred when you want to provide a common implementation for related subclasses.

Answer

Abstract classes can only be used for static methods, while interfaces can be used for dynamic methods.

Answer

Interfaces are faster to compile than abstract classes.

Question from the Java test

Explain the difference between interfaces and abstract classes in Java.