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parantheses in explicit casting

 
saravanan ragunathan
Ranch Hand
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when i use explicit casting without outer parantheses (Dog) animal.eat(); instead of ((Dog) animal).eat();
i am getting compilation error...what these parantheses tell to the compiler..how the compiler understand
this explicit casting with and without outer parantheses
 
Ankit Garg
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If you write (Dog) animal.eat(), 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...
 
Matthew Brown
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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.
 
It is sorta covered in the JavaRanch Style Guide.
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