How could I transform a initial value to another value with code java in SOAPUI?

Hi

I have the answer of a REST service.  The following REST service uses as input an output of the first REST service parameter.  But the value needs to be calculated with a java progran . How could I do that?

java code to convert an initial value to another

import  xxxx.TOTPTokenGenerator;
public class Prueba {

    public static void main(String args[]) throws Exception {
    
 TOTPTokenGenerator generator = TOTPTokenGenerator.instancia();
 System.out.println(generator.getCode(args[0]));
      }
}

Thanks you