public static long parseLong(byte[] bytes, int start, int length) {
    return parseLong(bytes, start, length, 10);
  }
Parses the string argument as if it was a long value and returns the
result. Throws NumberFormatException if the string does not represent a
long quantity.

@param bytes
@param start
@param length
         a UTF-8 encoded string representation of a long quantity.
@return long the value represented by the argument
@exception NumberFormatException
             if the argument could not be parsed as a long quantity.
serde/src/java/org/apache/hadoop/hive/serde2/lazy/LazyLong.java