code: public static void notNegative(final Integer input, final String inputName) {
          notNull(input, inputName);
  
          if (input < 0) {
              throw new IllegalArgumentException("a value of " + input.toString() + " was unexpected for " + maskNullArgument(inputName) + ", it is expected to be positive");
          }
      }
docs: Checks that the input value is non-negative
  @param input the input to check
  @param inputName the name of the input
  @throws IllegalArgumentException if input is null or if the input is less than zero