[jdom-interest] Request -- please allow all XML 1.1 conformant text in Element.se tText()

Elliotte Rusty Harold elharo at metalab.unc.edu
Sun Mar 7 17:35:33 PST 2004

At 9:11 AM +1100 3/8/04, Chris B. wrote:
>--"In order to better support the Open-Closed principle, all 
>features of a class are always available to subclasses in Eiffel, so 
>there is no notion of private as there is in Java and C++."--
>Many expert people don't agree with you. Read Meyer.

Have you read Meyer? If you have, you have severely misunderstood him 
at a very basic level. In Eiffel (and in Meyer's general philosophy 
of object oriented programming) "the invariants of all the parents of 
a class apply to the class itself" (OOSC, p. 570). In other words, an 
overriding method must satisfy the postconditions of the overridden 
method. This is trickier in Java than Eiffel because Java doesn't 
have inheritable postconditions. But even Eiffel also offers the 
ability to freeze a feature, roughly equivalent to Java's final. 
Meyer certainly does not recommend allowing subclasses unrestricted 
redefinition of superclass functionality, just the opposite in fact.

Also, can you give a page cite for that quote? I couldn't find it.


   Elliotte Rusty Harold
   elharo at metalab.unc.edu
   Effective XML (Addison-Wesley, 2003)

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