Type

The type of an inner class, when used as a variable or as a field, is the name of the containing class followed by a . and the name of the inner class.

class Car {
    class Speedometer {}
}

So a field containing an instance of Speedometer would have the type Car.Speedometer.

Car.Speedometer speedometer = ...;

The exception is if the inner class is referenced within the class that declares it. In that context you just need to write the name of the class;

class Car {
    // Car.Speedometer is not required
    // (it will work though)
    Speedometer speedometer;

    class Speedometer {}
}