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Set that only Items can be added

Joey Sanchez
Ranch Hand

Joined: Jun 23, 2011
Posts: 86

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.
Don't get me started about those stupid light bulbs.
subject: Set that only Items can be added