public Iterator<?> fieldIterator()
    {
        if (!isFieldListDataFormat())
            throw new IllegalArgumentException("Data format is not compatible");

        byte[] data = _event.getData();
        if (data.length != 0)
        {
            try
            {
                if (_iterator == null)
                    _iterator = new TibMsgIterator(data);
                else if (_iterator.hasNext())
                {
                    // don't reuse because it is probably still in use
                    _iterator = new TibMsgIterator(data);
                }
                else
                {
                    // this reuses an iterator and can be dangerous in some
                    // usage patterns
                    _iterator.reset(data);
                }
                return _iterator;
            }
            catch (TibException e)
            {
            }
        }

        return EmptyIterator;
    }