Posted by editor
on November 28, 2006 at 6:52 AM PST
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
When constructors need to be private
Sometimes when we get a not-so-stupid question, we need to expand the question as originally submitted, to give readers a little to chew on before they reach the discussion section. And that can be a little tricky when we already know the answer. It does require mentally placing one's self in the mind of someone who hasn't been programming in Java for a long time.
In other words, if I can forget the many times I've banged out a singleton pattern, I can take myself back to a place where the idea of a
private constructor didn't make sense. To the new programmer, this can be a valid conundrum: if you would need to have an instance of some class to call a private method on that class, and would need to call a private constructor to create such an instance, it seems like a logical impossibility.
Many of you see the hole in this reasoning (I'll bet you've written a few singleton patterns in your time, yes?), because within just an hour of posting today's Feature Article , there were already four substantial talkbacks. And I'll bet there are more uses to be discussed other than just the singleton. So please have a look at
(Not So) Stupid Questions 15: How Can a Constructor Be Private? and see if you can add something to the discussion.
In Java Today ,
the ossj-tck-foundation project has
graduated fom the incubator to a Java Enterprise project. The goal of the OSSJ TCK Foundation project is to ease creation of OSS/J TCKs by ensuring that the TCK builder can focus on building test cases and not having to worry about the 'plumbing' that is needed to bridge the 3 integration profiles (EJB, XML/JMS, Webservice) that are defined for all OSS/J APIs.
To celebrate the NetBeans 5.5 launch, NetBeans has put together the second edition of NetBeans Magazine , focusing on enterprise development. This edition of NetBeans Magazine covers a wide range of new features in NetBeans 5.5 and its main extensions, while also delving into core Java technologies. You can view this issue as a whole or as individual articles.
Java Puzzlers author Neal Gafter is back again with A Thread Pool Puzzler : "When I started using java.util.concurrent I was already somewhat comfortable with [its] concepts. But when I used it more intensely for production work in the Google Calendar server, I ran into a couple of 'gotcha' situations. I'd like to tell you about one in particular, in part because it might help you avoid the problem yourself, and in part because I believe this issue exposes some missing functionality in the concurrency framework."