Difference b/w interface and a class used in android with examples….the example will clear the use of these two and where to use a interface or a class
The key technical differences between an abstract class and an interface are:
An interface is an empty shell, there are only the signatures (name / params / return type) of the methods. The methods do not contain anything. The interface can’t do anything. It’s just a pattern.
Implementing an interface consumes very little CPU, because it’s not a class, just a bunch of names, and therefore there is no expensive look-up to do. It’s great when it matters such as in embedded devices.
Abstract classes, unlike interfaces, are classes. They are more expensive to use because there is a look-up to do when you inherit from them.
Abstract classes look a lot like interfaces, but they have something more : you can define a behavior for them.
While abstract classes and interfaces are supposed to be different concepts, the implementations make that statement sometimes untrue. Sometimes, they are not even what you think they are.
In Java, this rule is strongly enforced, while in PHP, interfaces are abstract classes with no method declared.
In Python, abstract classes are more a programming trick you can get from the ABC module and is actually using metaclasses, and therefore classes. And interfaces are more related to duck typing in this language and it’s a mix between conventions and special methods that call descriptors (the __method__ methods).