A number of readers have asked me for reference implementations of the stability and capacity patterns.

I've begun to create some free implementations to go along with Release It. As of today, it just includes a drop-in formatter that you can use in place of the java.util.logging default (which is horrible).

This formatter keeps all the fields lined up in columns, including truncating the logger name and method name if necessary. A columnar format is much easier for the human eye to scan. We all have great pattern-matching machinery in our heads. I can't for the life of me understand why so many vendors work so hard to defeat it. The one thing that doesn't get stuffed into a column is a stack trace. It's good for a stack trace to interrupt the flow of the log file... that's something that you really want to pop out when scanning the file.

It only takes a minute to plug in the SingleLineFormatter. Your admins will thank you for it.

Read about the library.

Download it as .zip or .tgz.

Agile, Architecture and the 5am Production Problem

This problem vexed me for several days. In this article, I ask whether we need to find new practices, consistent with agile values, that would let us prevent this type of problem. While the problem itself didn't arise from using agile methods---in fact, it was a distinctly non-agile project---I do wonder whether we can find an agile, pragmatic approach to architecture that would let us avoid this type of headache without incurring BAUF (Big Architecture Up Front).

Master Merlin's New I/O Classes

An introduction to the NIO classes added to Java 1.4 (which was code-named "Merlin"). A fun piece to write and an early source of information about this important package.

The "selector" architecture of asynchronous I/O in NIO was based on earlier UNIX constructs that I had used to multiplex keyboard, network, and inter-process communication in a single-threaded console application. This article let me dust off some of those old memories, while also appreciating how far we've come... that stuff was hard to do in straight UNIX/C programming!

The code in this article was written against the beta release of NIO. About three days after this article hit the front page, Sun released the GA version and broke all the sample code.

Test Infect Your Enterprise JavaBeans

This article presents a technique for what we now call in-container testing of EJBs, using a servlet to trigger the execution of unit tests.

This approach to unit testing worked for a time. Since J2EE 1.2, however, the separation of contexts between the container and the individual applications makes the specific configuration in the article ineffective.

Furthermore, I now believe that in-container testing is not a good approach. First, it requires too much startup and shutdown time, which makes you likely to run the tests less often. Second, it encourages context-dependence in both the unit tests and in the objects being tested.

Steve Jobs Made Me Miss My Flight
New tech meets security theater.

The Veteran and The Master
A parable of two programmers.

Too Much Abstraction
The benefits of peeling back layers of abstraction. Get grounded to avoid disconnects.

Don't Build Systems That Boink
Keys to building systems that survive encounter with the real world. This article was an early thread leading to Release It!.

Multiplier Effects
Multiplier effects can put you on the wrong end of the lever.