docs: public static String joinStrings(List<String> strings, boolean fixCase, char withChar) {
          if (strings == null || strings.size() == 0) {
              return "";
          }
          StringBuilder result = null;
          for (String s : strings) {
              if (fixCase) {
                  s = fixCase(s);
              }
              if (result == null) {
                  result = new StringBuilder(s);
              } else {
                  result.append(withChar);
                  result.append(s);
              }
          }
          return result.toString();
      }