Exception in thread "main" java.lang.Error: Unresolved compilation problems:
    Cannot instantiate the type Calculator2Service
    The method getCalculator2Port() is undefined for the type Calculator2Service

    at com.theopentutorials.ws.calc2.client.Calc2Client.main(Calc2Client.java:13)

package com.theopentutorials.ws.calc2.client;

import com.theopentutorials.ws.calc2.*;

public class Calc2Client {

    /**
     * @param args
     */
    public static void main(String[] args) {
        int a = 10;
        int b = 12;
        Calculator2Service calcService = new Calculator2Service();
        Calculator2 calc = calcService.getCalculator2Port();
        System.out.println(a + " + " + b + " = " + calc.add(a, b));
        System.out.println(a + " - " + b + " = " + calc.sub(a, b));

    }

}

public interface Calculator2 {

    public double add(double a, double b);
    public double sub(double a, double b);
}

Calculator2 getCalculator2Port(){
    Calculator2 c = new Calculator2(){
       public double add(double a,double b){
          return(a+b);
       }

       public double sub (double a, double b){
          return(a-b);
       }
    }
    return(c);
 }