docs: public static String join(Collection<String> s, String delimiter, boolean doQuote) {
          StringBuffer buffer = new StringBuffer();
          Iterator<String> iter = s.iterator();
          while (iter.hasNext()) {
              if (doQuote) {
                  buffer.append("\"" + iter.next() + "\"");
              } else {
                  buffer.append(iter.next());
              }
              if (iter.hasNext()) {
                  buffer.append(delimiter);
              }
          }
          return buffer.toString();
      }