code: public static <T> String joinAnd(final String delimiter, final String lastDelimiter, final Collection<T> objs) {
      if (objs == null || objs.isEmpty()) {
        return "";
      }
  
      final Iterator<T> iter = objs.iterator();
      final StringBuffer buffer = new StringBuffer(Strings.toString(iter.next()));
      int i = 1;
      while (iter.hasNext()) {
        final T obj = iter.next();
        if (notEmpty(obj)) {
          buffer.append(++i == objs.size() ? lastDelimiter : delimiter).append(Strings.toString(obj));
        }
      }
      return buffer.toString();
    }
docs: Like join, but allows for a distinct final delimiter.  For english sentences such
  as "Alice, Bob and Charlie" use ", " and " and " as the delimiters.
  
  @param delimiter     usually ", "
  @param lastDelimiter usually " and "
  @param objs          the objects
  @param <T>           the type
  @return a string