This is an introduction to developing Jython, just to get someone started. It doesn't cover the source code in any depth or discuss the design behind Jython. It's purely aimed at getting a development environment set up. It's definitely not complete so feel free to make it better!
Check out a copy of the Jython source with Mercurial, available on most *nix systems or with Cygwin on Windows.
You can use the command line tool hg, or GUI clients are available on most platforms.
To obtain the a copy of the current development source, clone the repo via:
hg clone http://hg.python.org/jython
Attach patches to issues in the Jython bug tracker.
Also, you can upload them to http://codereview.appspot.com (the Jython repository is already registered).
When Jython first followed CPython into use of Mercurial as the repository, it continued to reference a part of the CPython source at https://svn.python.org as a "sub-repository". This meant you still needed Subversion installed. As of 20 March 2012, the Jython Mercurial repository contains a snapshot of CPython libs in the 2.2, 2.5, and default branches.
You therefore only need the following advice if you are somehow working with an old repository.
The following advice is based on experience using Mercurial 1.9, Slik Subversion and Windows 7 (AMDx64). Other tools and operating systems exist. An installation that gives you the command 'svn' on your path is sufficient.
If you do not have Subversion installed (and on the PATH) the Mercurial hg clone command will terminate with the message:
abort: The system cannot find the file specified
at the point where it attempts to read the sub-repository, specified in the files .hgsub and .hgsubstate .
A second requirement is that Subversion should accept the SSL certificate from the site svn.python.org. If you have not used Subversion already to access the site, you may find that the hg clone command hangs at the point where it attempts to read the sub-repository. A simple solution is to visit the site once from the command line as follows:
svn info https://svn.python.org/projects/python/branches/release26-maint/Lib/
Subversion will issue a warning about the certificate, and you will be able to "accept permanently" the site's certificate. The Mercurial clone operation should not now hang.
If you see the sub-directory CPythonLib created in your local repository, then the call to Subversion by Mercurial was a success. (It can take a few minutes to complete.)
Ant is a Java-based tool used to build Jython from source.
Eclipse users, see Eclipse Ant notes
Download the latest version (Jython requires Ant 1.7 or later to build) and install it so Ant's bin directory is somewhere in your path.
To build Jython, run ant in the top-level Jython directory (which contains the Ant file build.xml).
The results of the build appear in the dist subdirectory.
The Jython build process generates an executable Bash script, dist/bin/jython, to make it easy to launch your build of Jython. It works on Unix-like platforms (including Mac OS X and Cygwin).
If you're using Windows without Cygwin, use the batch file dist/bin/jython.bat instead.
Now you're ready to run tests...
- There are a couple different places to find test cases
Jython's dist/Lib/test (populated by the build process)
Jython's bugtests subdirectory (included with the development sources)
Run a particular test, or the whole Python test suite with ant regrtest.
See TestingJython for some more details.
Note the following describes the current trunk/jython. If you are working from an older tag, src doesn't exist and src/com and src/org are moved up a level.
src/org : top level package for python
src/com : zxJDBC related sources
src/shell : launcher scripts
src/templates: java source generator & related templates, used to update portions of java classes elsewhere in the source tree
Demo : demo sources for the website and such
Lib : the python source files for Jython standard library implementations
Lib/test : test cases
Misc : random scripts which are not all used; some generate source
Tools : JythonC and Freeze
CPythonLib : Lib directory from the corresponding version of cpython, via svn:externals
bugtests : additional test cases covering bug reports
JythonDeveloperGuide/PortingPythonModulesToJython : A good starting task for a Jython developer
CodingStandards : The standards for writing Java code for Jython
PatchGuidelines : How to make a patch for submission to the tracker
How things work
ImplementNewType : Implementing a new type (a beginner's notes)
ImplementSequenceType : Implementing a new sequence type
JythonModulesInJava : How to write a Jython module in Java
PythonTypesInJava : How to make a Jython type in Java (2.5 and later), mostly about the type exposer
JythonClassesInJava : How to make a Jython class in Java (pre-2.2, deprecated)
JythonDeveloperGuide/ImplementingStrAndRepr : Tips for implementation of __str__ and __unicode__ in Java.
JythonDeveloperGuide/UsingPyNewStringFromPythonCode : On the corner case of converting a Java String to a Python String.
GeneratedDerivedClasses : gderived.py, a tool used when implementing new types
BufferProtocol : Design of a Jython equivalent to the CPython buffer protocol (buffer API)
MethodDispatch : An explanation of Jython method dispatch mechanism.
WebsiteBuilderSetup : How to get the pieces setup to edit and build the Jython website
VersionTransition : Why some tests are excluded in going to a new version and how to go about fixing them
JythonDeveloperGuide/RegressionTestNotes : Some notes the regression tests
JythonDeveloperGuide/PleaseAdoptMe : Tasks looking for volunteers
HowToReleaseJython : Checklist for building a release and updating the website
SvnToHgMigration : Notes on the migration to Mercurial
PerformanceEnhancements : Ideas on how to speedup Jython
CodebaseCleanup : Tasks/general guidelines on keeping the codebase clean