protected function _write()
{
$this->_writeInt($this->_getTransactionId());
$this->_writeBoolean(true);
foreach ($this->_operation_stack as $k => $operation_fields) {
$this->_writeByte(1);
foreach ($operation_fields as $field) {
$this->{$field[0]}($field[1]);
}
}
$this->_writeByte(0);
$this->_writeString('');
}