Re: Substring

Seamus MacRae wrote:


     Seems like this would demolish class inheritance. How is a
subclass supposed to initialize its own superclass' aspects? Calling
one of the superclass' factory methods and getting back an unextended
instance of the superclass doesn't seem helpful ...

    public class Super {
        /*private*/ Super() { }
        public static Super superFactory() {
            return new Super();
            // That might actually be wrong: where do Object's
            // factories get to do their thing?
        }
    }

    public class Sub extends Super {
        /*private*/ Sub() { }
        public static Sub subFactory() {
            // What goes here, to create and initialize
            // an object that has both Sub-nature and
            // Super-nature?
        }
    }

     For extra credit, suggest how the compiler -- more importantly,
the bytecode verifier -- can enforce your solution to the "factory
chaining" issue. (A discouraging note: finalizers are supposed to
chain, but neither the compiler nor the verifier even attempts to
ensure that they actually do. There might be a reason ...)

--
Eric.Sosman@sun.com