Java 8 default methods vs. non-abstract methods in abstract classes

Question

Java 8 interface default methods vs. non-abstract methods in abstract classes - are there any differences between the two (besides the differences of iface - class, visibili

Answer 1

Firstly Default methods allow you to add new methods to interface without breaking existing implementations.

Also take an example of Collections class which is a utility class for Collection interface right.

So using default methods we can now move all the utility methods as default implementation in the Collection itself, which will make more sense than making a separate class for such utilities.

Also you will be able to inherit methods from multiple interfaces, which could not have been done using plain abstract classes.