@Override
  public void transientInit(Configuration conf) throws HiveException {
    super.transientInit(conf);

    bytes = new byte[64];    // staging area for results, to avoid new() calls
  }
Superclass to support vectorized functions that take a long
and return a string, optionally with additional configuraiton arguments.
Used for bin(long), hex(long) etc.
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/FuncLongToString.java