code: public static boolean hasFunction(Object object, String functionName, Class[] parameters) {
          boolean result = false;
  
          try {
              Method method = object.getClass().getMethod(functionName, parameters);
  
              if (method != null) {
                  result = true;
              }
          } catch (NoSuchMethodException ex) {
              result = false;
          }
  
          return result;
      }
docs: Checks if Instance has specified function
  
  @param object       Instance which function would be checked
  @param functionName function name
  @param parameters   function parameters (array of Class)
  @return true if function is present in Instance