Should I explicitly declare static methods in Java 8 interfaces as "public static" instead of "static" only?

Question

Looking at some interfaces in the Java 8 APIs (Example: Stream) I saw that static methods are declared as public static, but default and abstract methods are not. From a technical point of view if I omit the public in static methods of interfaces I got something different of public access modifier?

Answer 1

The Java 8 Language specification states clearly that:

Every method declaration in the body of an interface is implicitly public. It is permitted, but discouraged as a matter of style, to redundantly specify the public modifier for a method declaration in an interface.

However, there is a new feature coming with Java 9 consisting in supporting private interface methods. These private methods will be useful for reusing a block of code that default methods could benefit from.

So I think that the usage of public in the Java APIs is an anticipation of this change to make method visibility explicit for the sake of precision. Consequently, even if Java 8 does not encourage it, you can consider this it as a new best practice. Further readings here.