On Tue, 15 Feb 2011, Roman Chyla wrote:
The python embedded in Java works really well on MacOsX and also
Ubuntu. But I am trying hard to make it work also on Scientific Linux
(SLC5) with *statically* built Python. The python is a build from
ActiveState.
You mean you're going to try to dynamically load libpython.a into a JVM ?
I have no idea if this can work at all.
If my understanding of static builds is correct, I'd imagine the only way
for this to work would be to statically compile the JVM (hotspot) and python
together.
But why all this ?
Andi..
So far, I managed to build all the needed extensions (jcc, lucene,
solr) and I can run them in python, but when I try to start the java
app and use python, I get:
SEVERE: org.apache.jcc.PythonException:
/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/lib-dynload/time.so:
undefined symbol: PyExc_IOError
I understand, that the missing symbol PyExc_IOError is in the static
python library:
bash-3.2$ nm
/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/config/libpython2.5.a
| grep IOError
0000000000004120 D PyExc_IOError
0000000000004140 d _PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
U PyExc_IOError
So when building JCC, I build with these arguments:
lflags + ['-lpython%s.%s' %(sys.version_info[0:2]),
'-L',
'/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/config',
'-rdynamic',
'-Wl,--export-dynamic',
'-Xlinker',
'--export-dynamic']
I just found instructions at:
http://stackoverflow.com/questions/4223312/python-interpreter-embedded-in-the-application-fails-to-load-native-modules
I don't really understand g++, but the symbol is there after the compilation
bash-3.2$ nm
/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/site-packages/JCC-2.7-py2.5-linux-x86_64.egg/libjcc.so
| grep IOError
0000000000352240 D PyExc_IOError
0000000000352260 d _PyExc_IOError
And when starting java, I do
"-Djava.library.path=/afs/cern.ch/user/r/rchyla/public/ActivePython-2.5.5.7-linux-x86_64/INSTALLDIR/lib/python2.5/site-packages/JCC-2.7-py2.5-linux-x86_64.egg"
The code works find on mac (python 2.6) and ubuntu (python2.6), but
not this statically linked python2.5 - would you know what I can try?
Thanks.
roman
PS: I tried several compilations, but I was usually re-compiling JCC
without building lucene etc again, I hope that is not the problem.
