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Void Wrapper Class

Abhimanyu Kumar

Joined: Nov 05, 2004
Posts: 12
Has anyone of you used the Void wrapper class ? I read that it does not wrap any primitive data type but it is used to represent void keyword. I'm curious to see some code using this class

Thanks In Advance,

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Ernest Friedman-Hill
author and iconoclast

Joined: Jul 08, 2003
Posts: 24168

The only place it's used is in the Java Reflection API. There's a class java.lang.reflect.Method, which Java uses to represent a Java method. You can ask a Method object what its return type is. It answers by returning a Class object. The Void class contains the constant Void.TYPE which is used to represent "void" in this context. That's it -- you're actually not allowed to create an instance of Void, so there's really nothing else this class can be used for.
[ November 05, 2004: Message edited by: Ernest Friedman-Hill ]

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Layne Lund
Ranch Hand

Joined: Dec 06, 2001
Posts: 3061
I don't think I've ever written a program that uses it. The primary use I see, though, is reflection. If you are interested in exploring this further, you should learn more about the Java Reflection API. I'm sure you can also use the Search utility here at the Big Moose Saloon to find previous discussions on reflect.



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