/**
* Add a new row to management. The lowest valued available row will be used.
*
* @return the row index of the newly added row
*/
public int addRow() {
int r;
if (m_openRows == null || m_openRows.isEmpty()) {
r = (m_firstId == 0 ? ++m_curId : --m_firstId);
} else {
int key = m_openRows.firstKey();
r = m_openRows.remove(key);
}
return r;
}
