I would agree...this sounds like a classpath problem. First you need to determine the package you used (defined at the top of your source file, most likely in this case it's in the default package). Then go to the root directory (if you used the default package the compiled file won't be in any subdirectories). Then from the command line you can run your program by typing java <classname with main method>.
If you used something other than the default package, like in the following:
To run the application, from the command line change to the root directory where you compiled the files (you should see the "foo" directory) and then type java foo.bar.Test.
Hope this helps.
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