Diff between ClassNotFoundException & NoClassDefFoundError

Yes but it's not at all clear what the difference is, is it?

Actually on further investigation it turns out that NoClassDefFoundError is thrown if the apparent name of the class according to its filename isn't the same as the binary name compiled into it.

See ClassLoader.defineClass().

ejpa at 2007-7-14 1:23:01 >

> ClassNotFoundException is thrown if you directly use

> a class which can't be found.

I think this must create compile time error wihich is "can not find the symbol", is not it ?

> NoClassDefFoundError is thrown if you directly use a

> class which directly or indirectly uses another class

> which can't be found.

This also can create compile time error

samue-1a at 2007-7-14 1:23:01 >

> No. We are discussing exceptions and errors which

> arise at run-time out of code which obviously must

> have compiled correctly at some point. Otherwise we

> couldn't be running it.

I know what you are discussing about.

I mean that : For instance you are using the instance of Frame class without importing java.awt package. So according to your claim(opinion), this create a run time error called ClassNotFoundException or NoClassDefFoundError. However, I claim that this can create compile time error absolutely called "can not find symbol". So I mean that be careful while doing generilizations.

Regards,

Mert

samue-1a at 2007-7-14 1:23:01 >

The important difference it that one's a checked Exception, the other is a run time error.

ClassNotFoundException is thrown in circumstances where it's likely to be due to a configuration file error or even someone typing in the wrong name.

NoClassDefFound is thrown only if your program is flawed or wrongly installed.

ClassNotFoundException is likely to be something your program can recover from. The other is not.

malcolmmca at 2007-7-14 1:23:01 >