When constructors need to be private... also:
Feature Article: (Not So) Stupid Questions 15: How Can a Constructor Be Private?
Java Today: NetBeans magazine #2, ossj-tck-foundation project, and a thread pool puzzler
Weblogs: Stacked image editor, CVM map, and extending EL syntax
Forum postings: SwingLabs gets search, Java EE application clients, and Thread.stop() versus application isolation