Provide backward compatibility with Python 2.7

[bcdev]

Many users have a lot of legacy code depending on Python 2.7 and thus hesitate to move to Python 3:

• http://programmers.stackexchange.com/questions/63859/why-do-people-hesitate-to-use-python-3
• http://stackoverflow.com/questions/8102987/if-python-3-is-the-newest-python-why-is-python-2-still-around

[bcdev]

Python 2 --> 3: https://docs.python.org/2/howto/cporting.html

Python 2.7 'distutils' requires Visual Studio on Windows (for Python 3.3, jpy uses the Windows SDK 7.1):

• Visual Studio 2011: SET VS90COMNTOOLS=%VS100COMNTOOLS%
• Visual Studio 2012: SET VS90COMNTOOLS=%VS110COMNTOOLS%

--> As we use MS Visual Studio Express we can only compile for 32-bit target platforms

[bcdev]

Here are the used functions that are either missing or incompatible in Python 2.7

• PyModule_Create() named Py_InitModule() with different parameters, easily fixed
• PyUnicode_AsUTF8(), PyUnicode_FromKindAndData(), PyUnicode_AsWideCharString() missing, must code a replacement which is not straight forward due to uncicode conversion
• Buffer.releasebufferproc() has different parameters, not checked effort yet

[forman]

Done for 0.7.2

[bulli92]

Hi Norman,

thanks a lot for the fast implementation. The installation is however not working properly for me jet. I installed all required dependencies.

If I then say

python setup.py install

I get:
(ipythondev)m300028@alexnotebook:jpy$ python setup.py install
Building a 64-bit library for a Linux system
Traceback (most recent call last):
File "setup.py", line 84, in
libraries = ['jvm', 'python' + sysconfig.get_config_var('VERSION') + sys.abiflags]
AttributeError: 'module' object has no attribute 'abiflags'

My understanding is that the 'abiflags' attribute is specific to python3.

However, if I do

sudo python setup.py install

I get ...
(ipythondev)m300028@alexnotebook:jpy$ sudo python setup.py install
[sudo] password for m300028:
Error: Environment variable "JDK_HOME" must be set to a JDK (>= v1.6) installation directory
(ipythondev)m300028@alexnotebook:jpy$ sudo python setup.py install
Error: Environment variable "JDK_HOME" must be set to a JDK (>= v1.6) installation directory

which is weird, as I have installed the most recent JDK and JDK_HOME is pointing to it ...

(ipythondev)m300028@alexnotebook:jpy$ echo $JDK_HOME
/usr/local/bin/jdk1.8.0_05

Any ideas?

Best,
Alex

[forman]

Yes, the attribute sys.abiflags is a Python 3 feature. Fixed.

However, if you sudo, you loose your environment settings and this is why you don't have "JDK_HOME" anymore.