Jakarta Commons Cookbook

Rating:
Summary: Great introduction to the various Jakarta Commons libraries
Review: If you have used any of the open-source technologies offered at apache.org, you've probably got a few of these libraries already. This is a great introduction to the <insert word that doesn't sound as obnoxious as "plethora" or "myriad" here> of tools and utilites that will make your routine java development easier.

While it is not a comprehensive book, each chapter takes a look at various areas of Java development and which of the Commons libraries provide classes and methods to handle common routines. Covered are things like Text Manipulation, JavaBeans utils, Collections (stuff that isn't in the offical JDK... yet) and Math functions. Personally, I didn't realize just how cool some of the Math functions are - so that was an interesting read. I like the fact that there was a lot of source examples in the book, too.

I think O'Brien does a nice job at balancing the Commons stuff with the topics that are better handled by a more focused book. For example, he just touches on XML and Log4J - so if you're looking for a book that has details on getting logging up, running and configured (for example), this isn't it.

If you want to know if you should incorporate any of the Jakarta Commons stuff in your development, this book will give you plenty of reasons why.

Rating:
Summary: Good Book.
Review: It's hard to write a review of a book like this.
The Commons are such a big group of components, you really cannot cover all of it. Tim does a good job of introducing you to them (+2). Unlike most books, this is very readable, using (for the most part) clear examples (watch out for the phantom 'Person' class) (+1).
The only draw-back I can really point to is that Commons is really designed to be straight forward and easy to understand, so an O'Reilly cookbook might be too indepth for this (-1). I like that I can read other posts by the author, related to Commons, in the ASF (+2).

Rating:
Summary: For numerical methods & high performance computing
Review: One of the beauties about Java, compared to earlier languages like C or Pascal, is the huge set of library classes that comes with the default distribution. An immense amount of code, all for free. Any experienced Java programmer knows this. But what if you could also get another set of free classes that extends the functionality even more? And has been well tested? O'Brien educates us about this - the Jakarta Commons. A nifty amount of heavy code. It can be highly worth your while to peruse this for useful classes.

Here is a brief excerpt of what is offered. Consider the default maths classes that come with Java. Important. But still very primitive compared to the decades of effort put into various mathematical libraries in other languages like Fortran. Of course, many of those tend to be proprietary. Now, in Commons, we have Maths classes. These can solve a linear system of equations. In other words, matrix arithmetic is implemented. Opens up entire regions of electrical circuit modelling and control systems theory, for example.

For statistics, simple regressions between two variables is now computed. And complex numbers can be explicitly handled with the ComplexMath class.

It can be appreciated that the new Commons maths classes fill longstanding gaps in the default maths ability of Java, which has been weak in numerical methods and high performance computing. It greatly strengthens the credibility of developing applications in those fields with Java.