import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;
import org.python.core.Py;
import org.python.core.PyObject;
import org.python.core.PyString;
import org.python.core.PySystemState;
import org.python.util.PythonInterpreter;

public class JythonEncodingIssue {

    static final String a = "a";
    static final String ae = "ä";

    public static void main(String[] args) throws Exception {

        // Write file.py into disk.
        String pythonProgram = "# -*- coding: utf-8 -*-\n"
                + "a = '" + a + "'\n"
                + "ae = '" + ae + "'\n";
        OutputStreamWriter outStream = new OutputStreamWriter(new FileOutputStream(new File("file.py")), "UTF-8");
        outStream.write(pythonProgram);
        outStream.close();

        // Put current working directory in sys.path to import from there.
        PySystemState sys = Py.getSystemState();
        sys.path.append(new PyString(System.getProperty("user.dir")));

        // Import the file created above and get a couple of variables from there.
        PythonInterpreter interp = new PythonInterpreter();
        interp.exec("import file");
        interp.exec("a = file.a");
        interp.exec("ae = file.ae");
        PyObject pyA = interp.get("a");
        PyObject pyAe = interp.get("ae");

        System.out.println("" + pyA);  // a
        System.out.println("" + pyAe); // ä
        System.out.println("" + a.equals(pyA.toString())); // true
        System.out.println("" + ae.equals(pyAe.toString())); // false !
    }

}