Jython :: which modules are available to PythonInterpreter and how to add more

Question

I am using the Jython 2.5.3 `PythonInterpreter` class to evaluate some simple scripts but when I need to import any non-core modules I get an exception. Do I have to add some jython library jars in the CLASSPATH? Narrow-down code that demonstrates the problem: ``` import org.python.core.*; import org.python.util.PythonInterpreter; public class JythonTest { public static void main(String args[]) throws Exception { String scriptA = "import json"; // "import datetime" fails as well PythonInterpreter pi = new PythonInterpreter(); PyCode code = pi.compile(scriptA); PyObject result = pi.eval(code); } } ``` Running the above with only jython-2.5.3.jar in the CLASSPATH fails with the following trace: ``` [java] ImportError: No module named json [java] [java] at org.python.core.Py.ImportError(Py.java:304) [java] at org.python.core.imp.import_first(imp.java:755) [java] at org.python.core.imp.import_module_level(imp.java:837) [java] at org.python.core.imp.importName(imp.java:917) [java] at org.p…

Accepted Answer

You seem to be using the Jython jar file that doesn't include the bundled Python files (the standard library in the `/Lib` folder). I believe it should work if you use the standalone jar instead. See

- http://fwierzbicki.blogspot.se/2012/08/jython-253-final-released.html

- http://wiki.python.org/jython/InstallationInstructions

Jython :: which modules are available to PythonInterpreter and how to add more

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