// Saves into data structure selected stations (including position) and links
for (Object cell : cells) {
if (cell instanceof JmtCell) {
celltmp = (JmtCell) cell;
key = ((CellComponent) celltmp.getUserObject()).getKey();
stations.put(key, sd.serializeStation(key));
location = mediator.getCellCoordinates(celltmp);
stationpositions.put(key, location);
// Initialize 'zero' as the upper-leftmost point of selected stations
// Will be used as a bias while pasting
if (zero == null) {