/**
* Deletes the user set
*/
public ActionForward delete(ActionMapping mapping, ActionForm form, HttpServletRequest req, HttpServletResponse resp) {
UserSetListForm userSetListForm = (UserSetListForm) form;
UserSetManager userSetManager = new UserSetManager(locale,session);
String[] ids = userSetListForm.getChoosen();
if (ids != null) {
for (String id : ids) {
UserSet userSet = userSetManager.getUserSet(Long.parseLong(id));
if (userSet != null) {
// security check