What's the advantage of making an inner class as static with Java?

Question

I have an inner class in my Java class.

When I run find bugs, it recom

Answer 1

An inner class, by default, has an implicit reference to an object of the outer class. If you instantiate an object of this from the code of the outer class, this is all done for you. If you do otherwise you need to provide the object yourself.

A static inner class does not have this.

That means it can be instantiated outside the scope of an outer class object. It also means that if you 'export' an instance of the inner class, it will not prevent the current object to be collected.

As a basic rule, if the inner class has no reason to access the outer one, you should make it static by default.