What is the difference between abstract classes and interfaces in Java?

Can you explain the difference between abstract classes and interfaces in Java?

Sure! In Java, an abstract class can have both abstract methods (without a body) and concrete methods (with a body), while an interface can only have abstract methods until Java 8, which introduced default methods.

Are there any restrictions on using abstract classes or interfaces?

Yes, a class can extend only one abstract class but can implement multiple interfaces. This is a key difference.

When should I use an abstract class instead of an interface?

Use an abstract class when you want to share code among closely related classes. Use an interface when you want to define a contract for classes that may not be related.

Can you give me an example of each?

Certainly! An abstract class could be Animal with a method makeSound(), while an interface could be Flyable with a method fly(). Classes like Bird can extend Animal and implement Flyable.