code: public static String concatStringWithDelimiter(String[] strings, String delimiter) {
          StringBuilder sbr = new StringBuilder();
          int size = strings.length;
          for (int i = 0; i < size - 1; i++) {
              sbr.append(strings[i]).append(delimiter);
          }
          sbr.append(strings[size - 1]);
          return sbr.toString();
      }
docs: Utility method to create a large String with the given delimiter.
  
  @param strings   Strings to concatenate.
  @param delimiter The delimiter to use to put between each string item.
  @return a large string with all items separated by given delimiter.