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

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