Message10324

Ran:

$ java -cp jython-2.7.0.jar org.python.util.jython -vv <<< "import os; os.getpid()"

Relevant message:

import: trying org.python.modules.posix.PosixModule as builtin modules in SysPathJavaLoader
import: 'posix' as org.python.modules.posix.PosixModule in builtin modules
Failed to load native POSIX impl; falling back on Java impl. Stacktrace follows.
java.lang.NoClassDefFoundError: Could not initialize class jnr.posix.POSIXFactory$DefaultLibCProvider$SingletonHolder

Looking at the jar that doesn't work:

$ unzip -l jython-2.7.0.jar | grep POSIXFactory
     1022  2014-12-12 09:23   jnr/posix/POSIXFactory$1.class
      894  2014-12-12 09:23   jnr/posix/POSIXFactory$DefaultLibCProvider$SingletonHolder.class
      774  2014-12-12 09:23   jnr/posix/POSIXFactory$DefaultLibCProvider.class
     6341  2014-12-12 09:23   jnr/posix/POSIXFactory.class

And the last one that did:

$ unzip -l jython-2.7.0b3.jar | grep POSIXFactory
      807  2012-12-02 22:32   jnr/posix/POSIXFactory$1.class
      862  2012-12-02 22:32   jnr/posix/POSIXFactory$DefaultLibCProvider$SingletonHolder.class
      833  2012-12-02 22:32   jnr/posix/POSIXFactory$DefaultLibCProvider.class
      863  2012-12-02 22:32   jnr/posix/POSIXFactory$LinuxLibCProvider$SingletonHolder.class
      825  2012-12-02 22:32   jnr/posix/POSIXFactory$LinuxLibCProvider.class
      869  2012-12-02 22:32   jnr/posix/POSIXFactory$SolarisLibCProvider$SingletonHolder.class
      833  2012-12-02 22:32   jnr/posix/POSIXFactory$SolarisLibCProvider.class
      887  2012-12-02 22:32   jnr/posix/POSIXFactory$WindowsLibCProvider$SingletonHolder.class
     1522  2012-12-02 22:32   jnr/posix/POSIXFactory$WindowsLibCProvider.class
     3660  2012-12-02 22:32   jnr/posix/POSIXFactory.class

Pushing those classes into the new jar allows jython to load the native posix implementation again:

$ cp jython-2.7.0.jar jython-2.7.0-berg.jar
$ mkdir jython-2.7.0b3
$ cd jython-2.7.0b3
$ unzip ../jython-2.7.0b3.jar
$ jar uf ../jython-2.7.0-berg.jar jnr/posix/*
$ cd ..
$ java -cp jython-2.7.0-berg.jar org.python.util.jython <<< "import os; os.getpid()"                           
15152

Interestingly, this happens with Java 8 (both OpenJDK and Oracle) but not with an old Java 7 install on the box.

$ java -version
openjdk version "1.8.0-internal"
OpenJDK Runtime Environment (build 1.8.0-internal-build_2015_03_04_15_08-b00)
OpenJDK 64-Bit Server VM (build 25.40-b25, mixed mode)
$ java -cp jython-2.7.0.jar org.python.util.jython <<< "import os; os.getpid()"                          
Jython 2.7.0 (default:9987c746f838, Apr 29 2015, 02:25:11) 
[OpenJDK 64-Bit Server VM (Oracle Corporation)] on java1.8.0-internal
Type "help", "copyright", "credits" or "license" for more information.
>>> import os; os.getpid()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'getpid'

$ /usr/bin/java -version
java version "1.7.0_79"
OpenJDK Runtime Environment (IcedTea 2.5.6) (7u79-2.5.6-0ubuntu1.14.04.1)
OpenJDK 64-Bit Server VM (build 24.79-b02, mixed mode)
$ /usr/bin/java -cp jython-2.7.0.jar org.python.util.jython <<< "import os; os.getpid()"
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