code: public Joining ellipsis(CharSequence ellipsis) {
          return new Joining(delimiter, ellipsis.toString(), prefix, suffix, cutStrategy, lenStrategy, maxLength);
      }
docs: Returns a {@code Collector} which behaves like this collector, but uses
  the specified ellipsis {@code CharSequence} instead of default
  {@code "..."} when the string limit (if specified) is reached.
  
  @param ellipsis the sequence of characters to be used at the end of the
  joined result to designate that not all of the input elements are
  joined due to the specified string length restriction.
  @return a new {@code Collector} which will use the specified ellipsis
  instead of current setting.