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checked Exception

kittu karan
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Joined: Mar 09, 2008
Posts: 63
What is checked Exception?How can we know what exception is checked or unchecked Exception?
Christophe Verré

Joined: Nov 24, 2005
Posts: 14688

A checked exception is an exception that you'll have to catch or rethrow, otherwise the compiler won't be happy. It's like saying that you're throwing eggs and there's nobody to catch them Checked exceptions extend the Exception class.
[ March 21, 2008: Message edited by: Christophe Verre ]

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Jun Wu

Joined: Mar 20, 2008
Posts: 14
Hi kiran peruka,the checked exception is a exception which you must try-catch or throws it,otherwise java compiler will angry! On the contrary ,you can try -catch unchecked exception ,or not,the complier doesn't complaint you !
Nikhil Raj

Joined: Mar 20, 2008
Posts: 16
A checked exception is any exception that the compiler will check whether you are handling or not. If a code throws a checked exception, you should use a try catch block to catch it or add a throws clause to the method.
otherwise the compiler will report an error.
Jelle Klap

Joined: Mar 10, 2008
Posts: 1951

You can indeed determine whether an exception is a checked exception or an unchecked exception at compile-time, by waiting for the compiler to complain about the catch or specify requirement. If you don't have that luxury (e.g. on an SCJP exam), you can also determine this by looking at the exception's type hierarchy. Only subclasses of java.lang.Error and java.lang.RuntimeException are unchecked. Everything else is checked.
[ March 21, 2008: Message edited by: Jelle Klap ]

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Ben Souther

Joined: Dec 11, 2004
Posts: 13410

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subject: checked Exception
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