Re: What have I done wrong
Re: What have I done wrong
Don't name packages java.anything as that conflicts with package names used by Oracle. Anything else is fine: people keep their package names from colliding with one another by using "backwards" web addresses like com.mycompany.me.myapp.gui or whatever. But for simple programs you don't expect to ever be used worldwide anything convenient will do.
Beyond that, post the actual code and say if it results in compiler messages or strange behaviour at runtime. That way there's a specific question we can address.