[ANN] JPE 2.0 The Java-Python Extension

Frederic Giacometti frederic.giacometti@arakne.com
Tue, 26 Feb 2002 13:12:01 -0800

This is the official announcement of the second version of JPE.

JPE (The Java-Python Extension) is a production-grade seamless
integration of Python and Java.
JPE lets you call Java objects and classes from Python, and vice-versa,
within the same process space. JPE is reentrant (cross-language
callbacks), and supports multi-threading concurently in Java and Python.

The reference web site for JPE is http://jpe.sourceforge.net

As compared to its first release:

1) Build
The build system of JPE  is based on a new build library (libplus):

  - Java and python are auto-detected from the command line, and
everything else is derived from there
(Java libraries, library paths...).

  - libplus generated its own makefiles, and runtime environment (env
variables) for the build and test phases; so there is no need to set-up

  - everything is now plateform-independant, and the same scripts are
used on Win32 and posix (no more GNU make / cygwin make required on

  - JPE has been ported to posix environments. However, a shared python
library is required on these platforms. You can build your onw, or use
the branched version of Python 2.1, named 'pythonx', which is provided
for these purposes.

  - JPE is distributed in source form from CVS. Substantial efforts have
been invested to provide a config and build environment that makes it
straightforward to configure, build from source, and test
multi-component, multi-platform software systems. Hopefully, that can be
one step ahead from the current autoconf or distutil systems.
Easily extensible to support arbitrary software components and tools,
libplus currently supports C, C++, Python, Java, and swig wrappers.
Libplus generates configuration-specific makefiles that chain software
component dependencies together, and provides runtime software/tool
configuration information.
Litteratly, this is an 'open-source' project :))

2) New capabilities of JPE, for the 2d release:

- Java bean support: Jbean properties are accessed as regular python

- Cross-language native array access: JPE integrates the bufarray python
extension type; a layer on top of the python buffer interface that
provides type-safe access to contiguous fixed-length C arrays (actually,
99% of the situations in scientific C or Fortran libraries).
This integration permits to safely access arrays by shared memory
reference between Java, Python, and C; while hidding the native memory

3) Acknowledgements:

Arakné, and The Molecular Graphics Laboratory at The Scripps Research

Benevolently yours,

Frédéric Giacometti