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Set that only Items can be added

Joey Sanchez
Ranch Hand

Joined: Jun 23, 2011
Posts: 88

Create a Set such that only Items can be added. Prove it.

I tried to do it Generic but as I expected a compile time error is thrown.
Is there another way of doing or it is just what the book is aking?

Praveen Kumar M K
Ranch Hand

Joined: Jul 03, 2011
Posts: 256
Java is strongly typed language and the compiler error is a testament to that.

You could also try this, just for learning's sake - Now that your Set can only accept Items and since any class in Java automatically is a subclass of Object, you could use type casting and introduce an instance of Object into the Set. See what happens then.
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subject: Set that only Items can be added
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