A Sensible Java Build Tool

I’ve been writing Java in one sense or another for a few years now.
 I learnt stuff at university, then used it in a few jobs.  I’ve written
Beans and Applets, and various bits of stuff in between. 
It’s fairly safe to say, that I like Java.  
One thing however, that’s been a pretty consistent bugbear in all the
time I’ve been writing Java, has been the classpath, and dependency…