ClassFile

The ClassFile collection of packages and utilities provides a means of importing Java classes and packages directly into Python, without the need for a Java virtual machine, so that the classes may be instantiated, accessed, run and manipulated just like Python classes, and that the resulting objects and methods can be accessed and manipulated just like Python objects and methods.

Quick Example

cd tests/

javac Value.java

../runclass.py Value

v.getValue() correct: 123
v.getValue() correct: 456
v.isPositive() correct: 1
v.isPositive() correct: 0
v.compare(-790) correct: -1
v.compare(-788) correct: 1
v.compare(-789) correct: 0
v.getValue() == v2.getValue() correct: 0
v2.add(-123) correct: 0
v2.getValue() correct: 255

java Value

v.getValue() correct: 123
v.getValue() correct: 456
v.isPositive() correct: true
v.isPositive() correct: false
v.compare(-790) correct: -1
v.compare(-788) correct: 1
v.compare(-789) correct: 0
v.getValue() == v2.getValue() correct: false
v2.add(-123) correct: 0
v2.getValue() correct: 255

Motivation

Pick one of the following:

• The need/desire to access Java libraries from Python without firing up Java virtual machines or switching to Jython (and thereby losing access to various CPython libraries).
• Static typing for the Python environment, albeit achieved by writing Java or other appropriate languages.
• Having an open source environment from top to bottom to run Java bytecode on.
• Experimentation around import hooks, bytecode generation; observation of different runtime and type systems interacting.