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please comment

 
Vinay Gangoli
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hi all....although this is a widely discussed topic..i was hoping i cud get some clear insights here. I was wondering how a class can extend a class and the class Object at the same time.
please help...thanks and regards
 
Ernest Friedman-Hill
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Every class extends either Object, or some other class. Object is thus ultimately the ancestor class of all other classes.
Does that answer your question?
 
fred rosenberger
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to be a little clearer, if class A extends class B, you can say "A is a B".
if B then extends C, "B is a C". by the transitive property, you can say "A is a C". and so on and so on...
if the class definition doesn't SAY it extends anything, it extends Object by default.
so, A extends B extends C extends Object.
[ March 01, 2004: Message edited by: fred rosenberger ]
 
Vinay Gangoli
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thanks for the quick replies....that cleared some air...What happens if A extends B and B extends A....is this a complier error ?. and if not how does class Object fit in ?
thanks
 
Ernest Friedman-Hill
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Yes, circular inheritance is an error, either at compile time or at runtime.
 
Vinay Gangoli
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thanks ...I got it now.
 
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