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Can anyone show me a working simple example (java + python code) of calling python script from java code by passing parameters and getting back the results?

elaspog
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  • this was the first result when I google it. http://bytes.com/topic/python/insights/949995-three-ways-run-python-programs-java – hcarrasko Dec 01 '14 at 19:03
  • I've already tried that, but the sample codes I've googled are not as simple I can understand, or simply not working. – elaspog Dec 01 '14 at 19:03
  • Already tried that. But "python.exec("number3 = number1+number2");" is not not a script beeing called. – elaspog Dec 01 '14 at 19:06
  • Ideally, since this is Java (you don't use Android, do you?), use Jython to run the script! – fge Dec 01 '14 at 19:07

1 Answers1

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Try using Java ScriptEngine to run the code as Jython.

Sample program:

import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;

public class Main {

     /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws ScriptException {
        ScriptEngine engine = new ScriptEngineManager().getEngineByName("python");

        // Using the eval() method on the engine causes a direct
        // interpretataion and execution of the code string passed into it
        engine.eval("import sys");
        engine.eval("print sys");

        // Using the put() method allows one to place values into
        // specified variables within the engine
        engine.put("a", "42");

        // As you can see, once the variable has been set with
        // a value by using the put() method, we an issue eval statements
        // to use it.
        engine.eval("print a");
        engine.eval("x = 2 + 2");

        // Using the get() method allows one to obtain the value
        // of a specified variable from the engine instance
        Object x = engine.get("x");
        System.out.println("x: " + x);
    }

}

You'll need to include the jython engine jar in your classpath. look for it here

Stav Saad
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