In Java Interface, we can have only final variables possible. We can also create static variables in Interface. But, at the same time we are not able to create static/final methods as Interface are only meant for Static Methods.
What is exactly the reason for not allowing static/final methods in Interface ?
A final method can't be overridden. That defies the purpose of having an interface if you cannot actually implement the method.
For the static part, see this question.