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Postings from August 2001
> They list two reasons to make your class final. One is security > (which might actually be valid, but I doubt it will hold up to > determined attack), the other though... > > You may also wish to declare a class as final for object-oriented > design reasons. You may think that your class is > "perfect" or that, > conceptually, your class should have no subclasses. > > The idea that a class is either 'perfect' or 'complete' has to be the > silliest, most arrogant thing I've ever heard! The only good justification I've heard for "final" is as a directive for optimization. If you declare a variable to be of a final type, then the compiler (JIT, or whatever) can resolve method dispatch at compile-time. If it is not final, then the compiler can make no such assumption because java code can load in extra classes later. However, there are probably some advanced techniques that allow optimization even when there is no "final". Remembering where optimizations were done, and undoing them if necessary, is one possibility. Perl would find this more difficult (there are many more ways to mess with the type system), so a "final" property may actually be useful. > Anyhow, just don't anyone suggest putting this in Perl 6. I know > where you live. Uh Oh :) Dave -- Dave Whipp, Senior Verification Engineer, Fast-Chip inc., 950 Kifer Rd, Sunnyvale, CA. 94086 tel: 408 523 8071; http://www.fast-chip.com Opinions my own; statements of fact may be in error.Thread Previous | Thread Next