[Jython-users] instance already instantiated error

[Andres Corrada-E. <co...@ci...>]

Hello,

I'm new to jython. I'm having problems creating a java class from python.
I took the example in jython.org that subclasses java.util.Random into a
python class: rand. If I then use jythonc to turn "rand" into a rand.class
and use it in a java program I get an error with this traceback:

at org.python.core.Py.TypeError(Py.java, Compiled Code)
at org.python.core.PyReflectedConstructor.__call__(PyReflectedConstructor.java, Compiled Code)
at org.python.core.PyReflectedConstructor.__call__(PyReflectedConstructor.java, Compiled Code)
at org.python.core.PyReflectedConstructor.__call__(PyReflectedConstructor.java, Compiled Code)
at org.python.core.PyObject.__call__(PyObject.java, Compiled Code)
at rand$_PyInner.__init__$2(rand.java, Compiled Code)
at rand$_PyInner.call_function(rand.java, Compiled Code)
at org.python.core.PyTableCode.call(PyTableCode.java, Compiled Code)
at org.python.core.PyTableCode.call(PyTableCode.java, Compiled Code)
at org.python.core.PyTableCode.call(PyTableCode.java, Compiled Code)
at org.python.core.PyFunction.__call__(PyFunction.java, Compiled Code)
at org.python.core.PyInstance.__init__(PyInstance.java, Compiled Code)
at org.python.core.Py.initProxy(Py.java, Compiled Code)
at rand.<init>(rand.java, Compiled Code)
at TestRand.main(TestRand.java, Compiled Code)

Traceback (innermost last):
  File "~corrada/qa/test/rand.py", line 0, in __init__
TypeError: instance already instantiated for java.util.Random

The rand.py is as shown in www.jython.org/docs/subclassing.html

and my TestRand.java class looks like this:

import rand;

class TestRand
{
    public static void main(String args[]){
        rand firstRand = new rand();
        System.out.println( firstRand.nextDouble() );
    }
}

What am I doing wrong?

Andres Corrada-Emmanuel
Senior Research Fellow
Center for Intelligent Information Retrieval
University of Massachusetts, Amherst