I don't know why you see that error, but you have to fully qualify Vector or import it. Otherwise, you will see an error complaining about not understanding vector. Use:
import java.util.Vector;
on the top line and see if that helps.
Other points, they're member variables, not globals.
Java does not permit global variables. Member variables can, of course, be private. There's nothing illegal in how you've declared them. However, member variables should start with a lower-case letter. Code is communication. By following conventions you communicate effectively!