What can you learn from testing? When you look beyond the red and the green, the fail and the pass, you can learn a lot more about the nature of the code and the nature of the problem domain. And there is a lot to learn — software development is called knowledge work for a reason.

What is the largest double that could in theory be produced by Math.random()? In this newsletter, we look at ways to calculate this based on the 48-bit random generator available in standard Java. We also prove why in a single-threaded program, (int)(Random.nextDouble() + 1) can never be rounded up to 2.

I'm not talking about the early adopters writing obscure code here -- that can probably be solved with a suitable style guide. I just debugged my way through an example that should have been trivial but I only figured out because:

In order for HTML5 to become the true user interface technology of the future, servers must be able to transparently push data to clients. People have been trying to do this for a long time, and WebSockets look like they will solve the problem once and for all.

A couple of weeks ago, I sent out a little quiz to my readers of The Java Specialists' Newsletter. No one managed to figure out what the code does without running it. Some managed to explain the result once they had run it. Perfect quiz for weeding out those job applicants you don't like. Especially in the banking industry. Enough hints :-)

My friend James Ward was explaining some of the struggles he had learning Scala, in particular partial functions.

Over a career, good programmers spend much more of their time in professional education than in their college classes. Much of this professional training is tied up with certification programs.

My JavaOne day three was just sessions. And the concert! But the sessions were good ones.

Accusoft Pegasus announces the acquisition of Adeptol, a leader in document viewing technology, and substantially all of its assets.

Day Two at JavaOne brought a few more interesting announcements.

The day one keynote convinced everyone that Java is moving forward. There are good things happening, good things on the horizon, and a few surprise changes-in-direction from Oracle.

Following up on my previous article, I create a super-simple example where a web page communicates with the server (written in Web.py) sending a JSON request object and receiving a JSON object as a response, which it uses to dynamically update the page. Afterwards, James Ward quickly loads the example into Heroku using their new Python support.

My thoughts on the battle between dynamic languages and those with Turing complete type systems after attending StrangeLoop.

In my article on JavaScript, I observed that we need a new language that generates good and safe JavaScript, so that you no longer have to think about either JavaScript issues or cross-browser problems. Little did I know that the solution(s) had already appeared in the form of JQuery and CoffeeScript.

One of the things I've loved about Python is that it was built as a community from the beginning. Language design decisions are genuinely discussed and struggled with as a community. But with Java, I've always felt like the adults were telling me what to think.

It appears we are stuck with JavaScript, at least in the near-to-mid term. Although the language is an abomination, some things are getting better. I discovered a couple of great lectures and a book that might change your perspective (a little) about the language.