Run a python application from within Java. These methods use Jython (which does not support python 3) and Runtime

app.py

import json


class Data:
    def fetch(self):
        return json.dumps({
            'name': 'scraper',
            'results': []
        })


def fetch():
    data = Data()
    return data.fetch()


if __name__ == '__main__':
    print(fetch())
    print("Success")

Launcher.java

package com.project.pythonIntegration;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.InputStreamReader;
import java.io.StringWriter;
import java.util.Properties;

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

public class Launcher {

	public static void main(String[] args) {

		integrationWithJython();
	}
	
	public static void integrationWithJython() {
    // WIP
		PythonInterpreter interpreter = null;

		Properties p = new Properties();
		p.setProperty("python.import.site", "false");
		interpreter.initialize(System.getProperties(), p, new String[] {});
		interpreter = new PythonInterpreter();

		interpreter.exec("results = fetch()");
		PyObject results = interpreter.get("results");
		System.out.println(results);
	}

	public static void integrationWithPython() {
		Runtime rt = Runtime.getRuntime();
		
		try {
			Process pr = rt.exec("python C:\\Users\\user.name\\eclipse-workspace\\PythonIntegration\\app.py");
			BufferedReader bfr = new BufferedReader(new InputStreamReader(pr.getInputStream()));
			String line = "";
			while((line = bfr.readLine()) != null) 
			{
				System.out.println(line);
			}
		} catch (Exception e) {
			System.out.println(e);
		}

	}
}