JythonTest.java

package gist;

import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.Iterator;

import org.apache.commons.lang.exception.ExceptionUtils;
import org.python.core.PyCode;
import org.python.core.PyFunction;
import org.python.core.PyList;
import org.python.util.PythonInterpreter;

public class JythonTest
{
    protected PythonInterpreter interpreter;

    public JythonTest()
    {
        interpreter = new PythonInterpreter();
    }

    public void runFile(String filename) throws IOException
    {
        interpreter.execfile(filename);
    }

    public void compileFileAndRun(String filename) throws IOException
    {
        FileReader reader = new FileReader(filename);
        PyCode code = interpreter.compile(reader);
        reader.close();
        interpreter.exec(code);
    }

    public void importAndRun(String filename) throws IOException
    {
        File file = new File(filename);
        String module = file.getName();

        if (module.endsWith(".py"))
            module = module.substring(0, module.length() - 3);

        StringBuffer cmd = new StringBuffer();
        cmd.append("import sys, imp\n");
        cmd.append("funcs = []\n");
        cmd.append("sys.path.insert(0, r'"
                + file.getAbsoluteFile().getParentFile().getAbsolutePath()
                + "')\n");
        cmd.append("try:\n");
        cmd.append("    f, p, d = imp.find_module('" + module + "')\n");
        cmd.append("    t = imp.load_module('" + module + "', f, p, d)\n");
        cmd.append("    for i in dir(t):\n");
        cmd.append("        if not i.startswith('_'):\n");
        cmd.append("            obj = getattr(t, i)\n");
        cmd.append("            if hasattr(obj, 'func_name'):\n");
        cmd.append("                funcs.append(obj)\n");
        cmd.append("except Exception, e:\n");
        cmd.append("    raise e\n");
        cmd.append("del sys.path[0]\n");
        interpreter.exec(cmd.toString());

        PyList funcs = (PyList) interpreter.get("funcs");
        for (Iterator<PyFunction> iterator = funcs.iterator(); iterator
                .hasNext();)
        {
            PyFunction func = iterator.next();
            func.__call__();
        }
    }

    public static void main(String[] args)
    {
        try
        {
            if (args.length < 1)
            {
                throw new Exception("Must provide at least 1 python file");
            }
            JythonTest tester = new JythonTest();
            for (String arg : args)
            {
                System.out.println("Execing: " + arg);
                tester.runFile(arg);
                System.out.println("=========\nCompiling and running: " + arg);
                tester.compileFileAndRun(arg);
                System.out.println("=========\nImporting and running: " + arg);
                tester.importAndRun(arg);
            }
        }
        catch (Exception e)
        {
            System.out.println(ExceptionUtils.getStackTrace(e));
            System.err.println("Error: " + e.getMessage());
        }
    }
}

test.py

from gist import Utils
from gist.p2 import Utils2

def run():
    print Utils.random()
    print Utils2.randomString(10)

if __name__ == '__main__':
    run()

Utils.java

package gist;

import java.util.Random;

public class Utils
{
    public static final double random()
    {
        return new Random(System.currentTimeMillis()).nextDouble();
    }
}

Utils2.java

package gist.p2;

import java.util.Random;

public class Utils2
{
    public static final String CHARS = "abcdefghijklmnopqrstuvwxyz0123456789";

    public static final String randomString(int length)
    {
        StringBuffer buf = new StringBuffer();
        Random random = new Random(System.currentTimeMillis());
        int charsLen = CHARS.length();
        for (int i = 0; i < length; ++i)
        {
            int nextInt = random.nextInt(charsLen);
            char c = CHARS.charAt(nextInt);
            if (random.nextBoolean())
                buf.append(String.valueOf(c).toUpperCase());
            else
                buf.append(c);
        }
        return buf.toString();
    }

}