Question

Previously I would always have thought a Vector was good to use for non-descript objects when length was unknown. As far as I was aware I thought it was thread-safe too

What would change that Vector shouldn’t be used anymore, and what is the alternative?

Answer 1

You should use ArrayList instead of Vector. Vector used internal synchronisation, but that is rarely good enough for actual consistency, and only slows down execution when it is not really needed.

Also see this stackoverflow question.