Calling Python Functions from Java

Java Program


import org.python.core.PyInstance;  
import org.python.util.PythonInterpreter;  
class PythonJava 
{  
   PythonInterpreter interpreter = null;  
   public PythonJava()  
   {  
      PythonInterpreter.initialize(System.getProperties(),System.getProperties(), new String[0]);  
      this.interpreter = new PythonInterpreter();  
   }  
   void execfile( final String fileName )  
   {  
      this.interpreter.execfile(fileName);  
   }  
   PyInstance createClass( final String className, final String opts )  
   {  
      return (PyInstance) this.interpreter.eval(className + "(" + opts + ")");  
   }  
   public static void main( String gargs[] )  
   {  
      PythonJava ie = new PythonJava();  
      ie.execfile("general.py");  
      PyInstance hello = ie.createClass("General", "7");  
      int f=Integer.parseInt(hello.invoke("factorial").toString());
      System.out.println("Factorial is "+f);
   }  
} 


# general.py
class General:
    def __init__(self,num):
        self.num=int(num)
    def factorial(self):
        f=1
        for i in range(1,self.num+1):
            f=f*i
        return f


Download the required JAR file 
http://www.java2s.com/Code/Jar/j/Downloadjythoncompletejar.htm

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