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main() & package question

Mark Supinski

Joined: May 14, 2010
Posts: 2
Hi All-

Working my way through S&B and ran into a behavior I don't understand.

Here's the code:

This code compiles fine. When trying to run the code, however, I get a runtime exception as follows:

My question is this: If I remove the package statements from this file and the associated Zoo.java file, the code runs fine. With the package statements, I get the runtime error above.

I can't find an explanation of this behavior anywhere. Can someone enlighten me?


Mark Supinski

Joined: May 14, 2010
Posts: 2
So I found my own solution.

package classes must be in a directory with a name corresponding to the package declaration. Moving the files into a foobar directory eliminated the runtime exception.

Note, however that java must be invoked from the root level. Thus, if one runs java Moo from within the foobar directory, the runtime exception occurs. If one steps back to the parent directory and runs java foobar/Moo it works properly.

Ankit Garg

Joined: Aug 03, 2008
Posts: 9435

java foobar/Moo it works properly.

I'm assuming you meant java foobar.Moo

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