All the data members in an interface are public final static only. i.e we can access those memebers without implementing the interface. They are just like static data members defined inside a class.
The methods declared inside the interface are not static, because we can't call any methods of an interface without implementing and also the methods are abstract inside an interface. Abstract and static wont go well
Classes(like data members) inside an interface by default are static, Coz we can't instantiate an interface to instantiate the nested class inside an interface.