Any good article about reference variables casting ...

Hi,
I am looking for a good and simple article on the reference variables downcasting (and yes I am searching the Internet too so please do not suggest that).
Please let me know if you know of any good article or if you can explain it well as I am having hard time to figure out when it is right and when it is used incorrectly.
Thanks,
Pritchard

Casting conversions are "right" when you need a reference of the particular type AND the underlying object is type-compatible with the declared variable.
"Downcasting" example:
Object o = new Object();
String s = (String) o; // BAD! The underlying object is not an instance of String
Object o = "foo";
String s = (String) o; // Okay.~

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10. interface Foo {}
11. class Alpha implements Foo { }
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14. public static void main( String[] args) {
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MyBugs_Bug wrote:
Doubt:
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MyBugs_Bug wrote:
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Any good article about reference variables casting ...

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