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The moose likes Beginning Java and the fly likes parantheses in explicit casting Big Moose Saloon
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parantheses in explicit casting

saravanan ragunathan
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Joined: Aug 02, 2010
Posts: 84

when i use explicit casting without outer parantheses (Dog); instead of ((Dog) animal).eat();
i am getting compilation error...what these parantheses tell to the the compiler understand
this explicit casting with and without outer parantheses

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Ankit Garg

Joined: Aug 03, 2008
Posts: 9465

If you write (Dog), it means you are trying to typecast the value returned by the eat method to Dog type. But the eat method has void return type thus it doesn't return anything so you can't typecast it...

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Matthew Brown

Joined: Apr 06, 2010
Posts: 4543

It's to do with the precedence. The "." operator has higher precedence than the cast, so it is performed first unless you put an extra set of brackets in. That's why you get the behaviour Ankit describes.
I agree. Here's the link:
subject: parantheses in explicit casting
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