code: public static String replaceLast(String source, String pattern,
                                       String replacement) {
          return replaceOne(source, pattern, replacement,
                            findLast(source, pattern));
      }
docs: Replaces the last exact match of the given pattern in the source
  string with the provided replacement.
  
  @param source the source string
  @param pattern the simple string pattern to search for
  @param replacement the string to use for replacing matched patterns
  
  @return the string with any replacements applied