Jython is an implementation of the Python programming language designed to run on the Java platform. The implementation was formerly known as JPython until 1999.[2]

Initial releaseJanuary 17, 2001; 22 years ago (2001-01-17)[1]
Stable release
2.7.3 / 2022-09-10
Written inPython and Java
Operating systemCross-platform
PlatformJava virtual machine
TypePython Programming Language Interpreter
LicensePython Software Foundation License (for older releases see License terms)
Websitewww.jython.org Edit this at Wikidata


Jython programs can import and use any Java class. Except for some standard modules, Jython programs use Java classes instead of Python modules. Jython includes almost all of the modules in the standard Python programming language distribution, lacking only some of the modules implemented originally in C. For example, a user interface in Jython could be written with Swing, AWT or SWT. Jython compiles Python source code to Java bytecode (an intermediate language) either on demand or statically.


Jython was initially created in late 1997 to replace C with Java for performance-intensive code accessed by Python programs, moving to SourceForge in October 2000. The Python Software Foundation awarded a grant in January 2005. Jython 2.5 was released in June 2009.[3]

Status and roadmapEdit

The most recent release is Jython 2.7.3. It was released on 10 September 2020 and is compatible with Python 2.7.[4]

Python 3 compatible changes are planned in Jython 3 Roadmap.[5]

Although Jython implements the Python language specification, it has some differences and incompatibilities with CPython, which is the reference implementation of Python.[6][7]

License termsEdit

From version 2.2 on, Jython (including the standard library) is released under the Python Software Foundation License (v2). Older versions are covered by the Jython 2.0, 2.1 license and the JPython 1.1.x Software License.[8]

The command line interpreter is available under the Apache Software License.


See alsoEdit

  • List of Java scripting languages
  • IronPython – an implementation of Python for .NET and Mono
  • PyPy – a self-hosting interpreter for the Python programming language.
  • JRuby – similar project for the Ruby programming language.
  • GraalVM - a polyglot runtime written in Java, has a Python 3 implementation


  1. ^ Wierzbicki, Frank (22 March 2015). "jython: 3d8067c56a1d NEWS". Retrieved 28 March 2015.
  2. ^ "JythonFaq/GeneralInfo - JythonWiki". 3 April 2014. Retrieved 28 March 2015.
  3. ^ Wierzbicki, Frank (16 June 2009). "Jython 2.5.0 Final is out!". Retrieved 2 July 2009.
  4. ^ "News". Jython. Retrieved 19 April 2020.
  5. ^ "Jython 3 Roadmap". Jython. Retrieved 14 October 2022.
  6. ^ "JythonFaq". Jython's project. Retrieved 5 July 2009.
  7. ^ "Differences between CPython and Jython". Jython's project. Retrieved 5 July 2009.
  8. ^ "The Jython License". Jython's project. Retrieved 9 February 2008.
  9. ^ "Introducing Ignition - Ignition User Manual 7.9 - Ignition Documentation". docs.inductiveautomation.com. Retrieved 24 April 2019.

External linksEdit