code: private static Class<?>[] convert(Class<?>[] classes) {
          Class<?>[] types = new Class<?>[classes.length];
          for (int i = 0; i < types.length; i++) {
              types[i] = convert(classes[i]);
          }
          return types;
      }
docs: Converts the provided array of classes to a version with 'boxed'
  primitives. This will convert {int, int, int} to {Integer, Integer,
  Integer}.
  
  @param classes converted classes
  @return converted types