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!
Contents
Mercurial
NOTE: The source code of Jython is now mirrored to Github, please see the next section "GIT" on how to contribute with pull requests.
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.
NetBeans, Eclipse and other Java IDEs also integrate Mercurial support. Eclipse users should see JythonDeveloperGuide/EclipseNotes.
Browse the source code on the Web at http://hg.python.org/jython or at the official mirror on BitBucket, at http://bitbucket.org/jython/jython.
To obtain the a copy of the current development source, clone the repo via:
hg clone http://hg.python.org/jython
It's easy to create your own fork of the repo on BitBucket, visit http://bitbucket.org/jython/jython and click on 'Fork' --- Please see the "GIT" section for our new GIT-based pull request process.
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).
GIT
Jython's source code is mirrored to https://github.com/jythontools/jython (a background sync runs every 5 minutes from hg.python.org)
You can use your favorite GIT client to clone the GIT repo, on the command line:
git clone https://github.com/jythontools/jython.git
- To submit patches, you should fork the github repo, create a special feature branch and submit a pull request on github.
The Jython developers will review and merge your pull request into the upstream Mercurial repo.
IDE Support
Because Jython is an Ant project, it's a bit tricky to configure an Integrated Development Environment (IDE) for it.
These notes should help:
Ant
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.
Tests
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.
Directory layout
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
Doc : the website documentation (see JythonDeveloperGuide/WebsiteBuilderSetup to build the http://jython.org website)
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
lib-python/<version> : Lib directory from the corresponding version of cpython
bugtests : additional test cases covering bug reports
Coding guidance
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/AttributeLookupMethods : Some explanation for the different methods to lookup attributes on PyObject.
JythonDeveloperGuide/ImplementingStrAndRepr : Tips for implementation of __str__ and __unicode__ in Java.
IntegerConversion : Basics of converting PyObject numbers to Java primitives
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.
Other stuff
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
Tasks
PerformanceEnhancements : Ideas on how to speedup Jython
CodebaseCleanup : Tasks/general guidelines on keeping the codebase clean