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concept of method overriding

Sandeep Tyagi

Joined: Mar 07, 2006
Posts: 3
why we can't use narrowing method in sub class on the case of method overriding
Thanks in advance

with Regards
Sandeep Tyagi
fred rosenberger
lowercase baba

Joined: Oct 02, 2003
Posts: 11152

i think it is because of polymorphism...

say you have a ClassA, with a public doSomething() method.

now, ClassB extends ClassA. say you could make B's doSomething() private.

now you make a collection of ClassA. you get a ClassB object, which you can put into the collection, since a ClassB is a ClassA.

now you iterate through the collection, calling doSomething() on every object. when you get to that ClassB, you're gonna have a problem...

There are only two hard things in computer science: cache invalidation, naming things, and off-by-one errors
I agree. Here's the link:
subject: concept of method overriding
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