where xyz is a class of mine own, and there's absolutely nothing wrong with it: indeed, if I uninstall NetBeans, reinstall it,
the very same project can be build without any modifications.
On the web I read some guy's posts regarding this issue, but it seems that there is not an effective solution.
The only workaround, besides of re-installing NetBeans, seems to uncheck "compile on save options". Indeed it works,
but I'd prefer to continue using compile on save feature -- it's very usefull for me.