/**
* Can group nodes so it can be all moved to a group (at least 1 available)
*/
public boolean canExecute() {
GraphElementsController gec = Lookup.getDefault().lookup(GraphElementsController.class);
boolean canGroup = gec.canGroupNodes(nodes);
if (canGroup) {
availableGroupsToMoveNodes = gec.getAvailableGroupsToMoveNodes(nodes);
return availableGroupsToMoveNodes != null && availableGroupsToMoveNodes.length > 0;
} else {
return false;