posted 20 years ago
Not especially.
Sure, there might be a (very slight) performance issue when the other class is first loaded, but only if is loaded from a remote location over a network, but that is really rare.
Much more likely is that the other class you are using may have lots of dependencies on yet other classes, even though the static method you are calling does not make use of them. This can lead to "code bloat", where a lot of unused classes need to be deployed with your application just to satisfy the compiler. I know of several "utilitiy" jars that have this problem.
Calling methods from other classes is generally a good thing, unless the other classes have taken on too many responsibilitie sand become bloated.