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overriding/poly morphic question

 
Tosin Adedoyin
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why does the comented line give me an error even though the class of l3 is tube why is it saying that it cannot find the test method in light . i thought it would use the one in tube
[ Jess Added UBB [CODE] tags to preserve whitespace, improve readibility ]
[ June 06, 2002: Message edited by: Jessica Sant ]
 
Thiru Thangavelu
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Because l3 is a reference to a superclass Light which doesn't have a test method. To call test() like this it has to be overridden. Since it is not overridden and you want to call the method in the subclass a cast is definitly needed.
Hope this helps.
 
Anna Dow
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Originally posted by Tosin Adedoyin:

why does the comented line give me an error even though the class of l3 is tube why is it saying that it cannot find the test method in light . i thought it would use the one in tube
[ Jess Added UBB
to avoid compiler errors
 
Tosin Adedoyin
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thank you but i thought that when a method is invoked on an object using a reference , it is the class of the current object denoted by the reference not the type of the reference that determines which method implementation will be executed ? so i thought the method test in tube should be called becase l3 is of class Tube
 
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