pass data from java to python and back jython

Question

I am using Jython to run a python script from Java. I am able to send data to the python script as command line arguments when I invoke the script using a PythonInterpreter .

Now I want to call a Java method from within the Jython script, passing a List as a method argument. How do I do that?

Answer 1

I am posting code for both passing of data from Java -> Python and Python -> Java. Hope this helps someone,, In this. String array "s" is passed to python script and from python, "city" list is passed from python to Java through function call getData().

JavaProg.java:

import org.python.core.PyInstance;
import org.python.util.PythonInterpreter;


public class JavaProg
{
    static PythonInterpreter interpreter;

   @SuppressWarnings("resource")
public static void main( String gargs[] )
   {
      String[] s = {"New York", "Chicago"};
      PythonInterpreter.initialize(System.getProperties(),System.getProperties(), s);
      interpreter = new PythonInterpreter();
      interpreter.execfile("PyScript.py");
      PyInstance hello = (PyInstance) interpreter.eval("PyScript" + "(" + "None" + ")");
   }

   public void getData(Object[] data)
   {
       for (int i = 0; i < data.length; i++) {
           System.out.print(data[i].toString());
    }

   }
}

PyScript.py:

import JavaProg
class PyScript:
    def __init__(self,txt):
        city = []
        for i in range(0,len(sys.argv)):
            city.append(str(sys.argv[i]))
        jObj = JavaProg()
        jObj.getData(city)
        print "Done!"