code: public static DateFormat getRfc1123DateFormat() {
          DateFormat format = new SimpleDateFormat(
                  "EEE, dd MMM yyyy HH:mm:ss z", Locale.ENGLISH);
          format.setLenient(false);
          format.setTimeZone(TimeZone.getTimeZone("UTC"));
          return format;
      }
docs: Creates a new instance of a <code>DateFormat</code> for RFC1123 compliant dates.
  <br>
  Should be stored for later use but be aware that this DateFormat is not Thread-safe!
  <br>
  If you have to deal with dates in this format with JavaScript, it's easy, because the JavaScript
  Date object has a constructor for strings formatted this way.
  @return a new instance