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Doubt

Mary Cole
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Joined: Dec 02, 2000
Posts: 362
Hi,

Why does line 3 cause Class Cast Exception where as line 4 doesn't

Thx
[ April 06, 2004: Message edited by: Mary Cole ]
Ashok C. Mohan
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Joined: Dec 03, 2003
Posts: 75
In line 3 u r trying to cast a base class object to a derived class,which causes the compile time error,as this does not make any sense.(Only derived class objects can be casted to base class objects.
In line 4 though u r trying to cast the interface reference to the base class,the underlying object to which the reference i is pointing is a base class object,so casting a base class object to itself does not cause a compile time error.


SCJP 1.4
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It is sorta covered in the JavaRanch Style Guide.
 
subject: Doubt