Major changes in the core of the Java Simon v2

While there are some important extensions to the Java Simon (JMX, Spring integration, etc.) there are a few important changes in the core part of the API that are probably even more important. If you've already managed to use Java Simon 1 I strongly suggest that you use version 2 even in its alpha stages. The thing is:

• If your project is finished or close to finish (month or two) stay with version 1.
• If your project continues and you're just experimenting with Simon, definitely use version 2! There is v2-alpha1 which is basically rework of the v1 after a few changes in Stopwatch. If there is newer alpha out (check Featured Downloads on the right on our project page) take that one of course, because it contains more features from v2.
• Version 2 is planned to be out during March or April 2009, which is really soon.

Now what are the changes and why we made them?

• Important change happened in the Stopwatch. While in the v1 it contained various start/stop methods that took care of multi-threaded environment now it has only one start method and this start doesn't return this anymore but it returns new Split object instead. You have to take care of the Split object, you have to take care of your multi-threading, you have to call stop method on the Split. This makes our code safer as the Stopwatch doesn't contain internal maps that were prone to memore-leaks if client forgot to stop some split. Thanks to Erik van Oosten and his great Java Simon evaluation.
• Based on the same post we changed sample methods so that they return Java Bean objects now instead of the field.
• While in v1 you had to use SimonManager now you can use non-static Manager implementation directly. SimonManager still stays your favourite convenient class full of static methods, of course. ;-) This allows to have multiple separeated Simon hierarchies which may be handy in Java EE environment.
• To provide some extensibility for the API we introduced Callback interface. This allows to hook onto various events and process these events in any way you want - to log them, send JMX notifications, whatever.

There are more features to come with version 2 and I covered only those in the core part of the API. Stay tuned, download, use, test, let us know what you think. :-)