Using a Class From An Unused Java Package

Using a Class From An Unused Java Package

I have that lines of code at my application:
return "Service is alive since: " +
TimeUnit.MILLISECONDS.toMinutes(mxBean.getUptime()) + " minutes";
it uses that package:
import java.util.concurrent.TimeUnit;
My application is a web application. Does it means that I have something
wrong logically if I use something from concurrent package at a web
application?