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dolly shah
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Joined: Jun 18, 2007
Posts: 383

Z & Y are sibling objects here. Line 1 fails at runtime but why it compiles?

SCJP-1.5<br />SCWCD-1.4
ahmed yehia
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Joined: Apr 22, 2006
Posts: 424
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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Joined: Jun 18, 2007
Posts: 383
Thanks Ahmed I got it. I was little confuse.
yogesh sood
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Joined: Aug 31, 2000
Posts: 108

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

If its green its biology if its stinkks its chemistry if it has numbers it is Maths and if it doesn't work its TECHNOLOGY
camilo lopes
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Joined: Aug 08, 2007
Posts: 202
You can not convert a car on a bike, only because both are vehicles. See the problem that prevents the compiler?
I hope I have helped!

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