The way people want to see their timeline has changed very fast in the last several years.Now instead of seeing timestamp people are more interested is seeing something like : “in 3 minutes!” etc etc.
The best way to do this in java is to use http://ocpsoft.com/prettytime/ , which allow you to use it in various variety of ways e.g. : PrettyTime.NET, PrettyTime Grails Plug-in, PrettyTime with JSP .