GeezerVison

Simple but effective tool to translate Java source code into Python.

The java2python package can translate any syntactically valid Java source code file. The generated Python code is not guaranteed to run, nor is guaranteed to be syntactically valid Python. However, java2python works well many cases, and in some of those, it creates perfectly usable and workable Python code.

The generated code targets Python 3.14+, and java2python itself requires Python 3.14+. For more information, read the introduction. To install (with uv), refer to the installation page.

There are lots of docs, plenty of tests, and many options for controlling code generation.

If you're looking for old releases, check the downloads link above.

Here's a very simple example:

$ cat HelloWorld.java

// This is the HelloWorld class with a single method.
class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, world.");
    }
}

Next we run our program:

$ uv run j2py HelloWorld.java

#!/usr/bin/env python3
""" generated source for module HelloWorld """
#  This is the HelloWorld class with a single method.
class HelloWorld:
    """ generated source for class HelloWorld """
    @classmethod
    def main(cls, args):
        """ generated source for method main """
        print("Hello, world.")


if __name__ == '__main__':
    import sys
    HelloWorld.main(sys.argv)