public interface AnInterfaceOperations {
    ... AnOperation (...) throws ...;
}

public interface AnInterface extends AnInterfaceOperations ... { }

abstract public class AnInterfaceHelper {
    public static void insert (Any a, AnInterface t) {...}
    public static AnInterface extract (Any a) {...}
    public static AnInterface read (InputStream is) {...}
    public static void write (OutputStream os, AnInterface val) {...}
    ...

    public static AnInterface narrow (org.omg.CORBA.Object obj) {...}
    public static AnInterface narrow (java.lang.Object obj) {...}
}

final public class AnInterfaceHolder implements Streamable {
    public AnInterface value;
    public AnInterfaceHolder () { }
    public AnInterfaceHolder (AnInterface initial) {...}

    ...
}