public void roomOccupancyReport()//no filters
    {
        int i, param = -1;
        Scanner sc = new Scanner(System.in);
        Room r;
        String criteria = "none";

        System.out.println("Search by:");
        System.out.println("\t1. No criteria");
        System.out.println("\t2. Floor");
        System.out.println("\t3. Occupancy");
        System.out.print("Enter choice: ");
        i = sc.nextInt();

        switch(i)
        {
            case 1:
                criteria = "none";
                break;
            case 2:
                criteria = "floor";
                System.out.println("Enter floor: ");
                param = sc.nextInt();
                break;
            case 3:
                criteria = "occupancy";
                System.out.println("\t1. Vacant rooms");
                System.out.println("\t2.. Occupied rooms");
                System.out.println("\t3. Reserved rooms");
                System.out.println("\t4. Under-maintenance rooms");
                System.out.println("Enter choice: ");
                int choice = sc.nextInt();
                switch(choice)
                {
                    case 1:
                        param = Room.VACANT;
                        break;
                    case 2:
                        param = Room.OCCUPIED;
                        break;
                    case 3:
                        param = Room.RESERVED;
                        break;
                    case 4:
                        param = Room.UNDER_MAINTENANCE;
                        break;
                    default:
                        System.err.println("Invalid choice.");
                        param = -1;                }

        }


        System.out.println("Room Occupancy:");
        for (i= 0; i<rooms.size();i++)
        {
            r = rooms.get(i);
            if (searchByCriteria(param, criteria, r))
                r.showRoom();
        }
    }