code: public static int toIntValue(final Character ch) {
          Validate.isTrue(ch != null, "The character must not be null");
          return toIntValue(ch.charValue());
      }
docs: <p>Converts the character to the Integer it represents, throwing an
  exception if the character is not numeric.</p>
  
  <p>This method converts the char '1' to the int 1 and so on.</p>
  
  <pre>
  CharUtils.toIntValue('3')  = 3
  CharUtils.toIntValue(null) throws IllegalArgumentException
  CharUtils.toIntValue('A')  throws IllegalArgumentException
  </pre>
  
  @param ch  the character to convert, not null
  @return the int value of the character
  @throws IllegalArgumentException if the Character is not ASCII numeric or is null