jvm documentation


Python bridge for the Java Virtual Machine.


jvm is a bridge between Python and JVM, allowing these to intercommunicate.
It is an effort to allow Python programs full access to Java class libraries.

PyPI record.


jvm package is closely based on the jni Python package.

What is jvm:

jvm is an effort to allow Python programs full access to Java class libraries.
This is achieved not through re-implementing Python, as Jython has done, but rather through interfacing at the native level in both virtual machines.

Eventually, it should be possible to replace Java with python in many, though not all, situations. JSP, Servlets, RMI servers and IDE plugins are good candidates.

Once this integration is achieved, a second phase will be started to separate the Java logic from the Python logic, eventually allowing the bridging technology to be used in other environments, I.E. Ruby, Perl, COM, etc …

Known Bugs/Limitations :
  • Java classes outside of a package (in the <default>) cannot be imported.

  • Because of lack of JVM support, you cannot shutdown the JVM and then restart it.

  • Some methods rely on the “current” class/caller. Since calls coming directly from python code do not have a current class, these methods do not work. The User Manual lists all the known methods like that.



To install run:

python -m pip install --upgrade jvm



  • Development is strictly based on tox. To install it run:

    python -m pip install --upgrade tox

Visit development page.

Installation from sources:

clone the sources:

and run:

python -m pip install ./jvm

or on development mode:

python -m pip install --editable ./jvm


Copyright (c) 2004-2022 Adam Karpierz
Licensed under CC BY-NC-ND 4.0
Licensed under proprietary License
Please refer to the accompanying LICENSE file.


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