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casting

 
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Z & Y are sibling objects here. Line 1 fails at runtime but why it compiles?
 
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Z y2 = (Z)y; //line 1

'y' is a variable of type 'X' that refers to an object of type 'Y' and you are casting it to type 'Z' which is a sub class of 'X' so it pass at compile time. Had it been of type 'Y' Not 'X' then it wouldnt compile.
 
dolly shah
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Thanks Ahmed I got it. I was little confuse.
 
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Dolly,

You should have look at this from Corey, to understand how it works for Interfaces.

 
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You can not convert a car on a bike, only because both are vehicles. See the problem that prevents the compiler?
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