Method saveorder

/**
 * Method to update order of table rows
 *
 * @param   array  $idArray   id numbers of rows to be reordered.
 * @param   array  $lftArray  lft values of rows to be reordered.
 *
 * @return  integer|boolean  1 + value of root rgt on success, false on failure.
 *
 * @since   1.7.0
 * @throws  \Exception on database error.
 */
public function saveorder($idArray = null, $lftArray = null)
{
    try {
        $query = $this->_db->getQuery(true);
        // Validate arguments
        if (\is_array($idArray) && \is_array($lftArray) && \count($idArray) == \count($lftArray)) {
            for ($i = 0, $count = \count($idArray); $i < $count; $i++) {
                // Do an update to change the lft values in the table for each id
                $query->clear()->update($this->_tbl)->where($this->_tbl_key . ' = ' . (int) $idArray[$i])->set('lft = ' . (int) $lftArray[$i]);
                $this->_db->setQuery($query)->execute();
                if ($this->_debug) {
                    $this->_logtable();
                }
            }
            return $this->rebuild();
        } else {
            return false;
        }
    } catch (\Exception $e) {
        $this->_unlock();
        throw $e;
    }
}