code: public static Long valueOf(String s, int radix) throws NumberFormatException {
          return Long.valueOf(parseLong(s, radix));
      }
docs: Returns a {@code Long} object holding the value
  extracted from the specified {@code String} when parsed
  with the radix given by the second argument.  The first
  argument is interpreted as representing a signed
  {@code long} in the radix specified by the second
  argument, exactly as if the arguments were given to the {@link
  #parseLong(java.lang.String, int)} method. The result is a
  {@code Long} object that represents the {@code long}
  value specified by the string.
  
  <p>In other words, this method returns a {@code Long} object equal
  to the value of:
  
  <blockquote>
  {@code new Long(Long.parseLong(s, radix))}
  </blockquote>
  
  @param      s       the string to be parsed
  @param      radix   the radix to be used in interpreting {@code s}
  @return     a {@code Long} object holding the value
  represented by the string argument in the specified
  radix.
  @throws     NumberFormatException  If the {@code String} does not
  contain a parsable {@code long}.