public boolean add( String id, String name, String password, String identityID, String institutionID, enumSet.Position work) throws RemoteException { List<UserPO> userList = this.list; UserPO po = new UserPO(id, name, password, identityID, institutionID, work); for (UserPO temp : userList) { if (temp.getId().equals(po)) { return false; } } userList.add(po); UserDS.add(po); return true; }