code: public static String substringAfter(String input, String substring) {
          int index = input.indexOf(substring);
          if (index == -1) {
              return "";
          } else {
              return input.substring(index + substring.length());
          }
      }
docs: Returns a subset of a string following the first occurrence of a specific substring.
  <p>If the substring is empty, it matches the beginning of the input string and the
  entire input string is returned. If the substring does not occur, an empty string is returned.
  
  @param input     the input string on which the substring function is applied
  @param substring the substring that delimits the beginning of the subset
  of the input string to be returned
  @return a substring of the input string that starts at the first character after the specified substring