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Joined: Feb 06, 2004
Posts: 7
We're working on a project using Java and Python. While executing PyInterpreter.initialize() we encountered some problems.
The code we are using looks like this:
import java.util.*;
import org.python.util.*;
import org.python.core.*;
public class SimpleEmbedded {
public static void main(String []args) throws PyException {
PythonInterpreter interp;
Properties props=new Properties();
interp = new PythonInterpreter();
This code generates the following error-message:
Exception in thread "main" java.lang.NullPointerException
at org.python.core.PyJavaClass.lookup(PyJavaClass.java:43)
at org.python.core.PyObject.<init>(PyObject.java:46)
at org.python.core.PySingleton.<init>(PySingleton.java:8)
at org.python.core.PyNone.<init>(PyNone.java:10)
at org.python.core.PySystemState.initStaticFields(PySystemState.java:396)
at org.python.core.PySystemState.initialize(PySystemState.java:375)
at org.python.core.PySystemState.initialize(PySystemState.java:348)
at org.python.util.PythonInterpreter.initialize(PythonInterpreter.java:40)
at SimpleEmbedded.main(SimpleEmbedded.java:16)
Can anyone help us ?
Ann Carpentier
Kenny Mees
Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
I first changed the python.path property string to have the value "c:\\jython-2.1\\Lib" appropriate to my system. I get the following output when compiling and running your program:

That is, it compiles and runs without any problem. I'm using java 1.4.2 on Windows NT4

By the way would you please change your displayed name to conform to JavaRanch's Naming Policy. You can change it here.
[ February 06, 2004: Message edited by: Barry Gaunt ]

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Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
And the following compiles and runs successfully:

Here's the console output:

Joined: Feb 06, 2004
Posts: 7
Dear Barry,
Although we think we tried everything, including the steps you gave us in your reply, we tried one more time with your instructions and guess what...

Thank you very much for your quick reply and help.
Ann Carpentier
Kenny Mees
[ February 06, 2004: Message edited by: Ann & Kenny ]
I agree. Here's the link: http://aspose.com/file-tools
subject: PythonInterpreter.initialize
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