A default method is a method defined within an interface with the default keyword in which a method body is provided.
The following are the default interface method rules you need to be familiar with:
1. A default method may only be declared within an interface and not within a class or abstract class.
2. A default method must be marked with the default keyword. If a method is marked as default , it must provide a method body.
3. A default method is not assumed to be static , final , or abstract , as it may be used or overridden by a class that implements the interface.
4. Like all methods in an interface, a default method is assumed to be public and will not compile if marked as private or protected.
If a class implements two interfaces that have default methods with the same name and signature, the compiler will throw an error.