Real-world Jython applications

I recentl开发者_高级运维y started learning Python. Not yet ventured into coding. During one of my learning sessions, i came accross the term Jython.

I googled it & got some information.

I would like to know if anyone has implemented any real-world program using Jython.

Most of the time, Jython isn't used directly to write full read-world programs, but a lot of programs actually embed Jython to use it as a scripting language.

The official Jython website gives a list of projects, some written in Jython, others using Jython for scripting: http://wiki.python.org/jython/JythonUsers

I am writing a full application in Jython at the moment, and would highly recommend it. Having all of the Java libraries at your disposal is very handy, and the Python syntax and language features actually make using some of them easier than it is in Java (I'm mostly talking about Swing here).

Check out the chapter on GUI Applications from the Jython book. It does a lot of comparisons like 'Look at all this Java code, and now look at it reduced to Python code of half the length!'.

The only caveats I've found are:

• Jython development tends to run slightly behind Python, which can be annoying if you find a cool way of doing something in Python, only to discover it's not supported in the current Jython version.
• Occasionally you might have hiccups with the interface between Python and Java (I have a couple of unsolved problems here and here, although there are always workarounds for this kind of thing).
• Distribution is not as simple as it could be, although once you figure out how to do it, it's fairly painless. I recommend following the method here. It essentially consists of:
  1. Exploding jython.jar and adding your own modules into it.
  2. Writing and compiling a small Java class that creates a Python interpreter and loads up your Python modules.
  3. Creating an executable .jar file consisting of the jython.jar modules, your own Python modules, and the Java class.

Jython really shines for dependency injection.

You know those pesky variables you have to give your program, like

• file system paths
• server names
• ports

Jython provides a really nice way of injecting those variables by putting them in a script. It works equally well for injecting java dependencies, as well.

WebSphere and WebLogic use it as their default scripting engine for administrative purposes.

A lot of other Oracle products ship it as part of their "oracle_commons" module (Oracle Universal Installer, Oracle HTTP Server etc). It's mostly version 2.2 being deployed though, which is a bit old and clunky.

There is a list of application that uses jython at http://wiki.python.org/jython/JythonUsers