public override void Execute() { double a = 2; double b = 3; double c = Math.PI / 2; ImportPackage("JavaClass"); IJavaObject javaClass = JVM.New("JavaClass") as IJavaObject; IJavaObject res = (IJavaObject)javaClass.Invoke("helloWorld"); //string shall be converted because is not a native string hello = (string)res.ToPrimitive(); double result = (double)javaClass.Invoke("add", a, b); double sin = (double)javaClass.Invoke("sin", c); Console.WriteLine("{0} {1} + {2} = {3} and sin({4:0.0000000}) = {5:0.00000000}", hello, a, b, result, c, sin); Console.WriteLine("Press Enter to exit"); Console.ReadLine(); }