如何更新房間數量？

Question

目前，我想在預訂添加到數據庫后更新我的房間可用性，但我現在面臨的問題是，我不知道如何在預訂后更新房間數量。

我需要的解決方案是，當我輸入房間數量並添加時，房間數據庫將減去房間數量。

DA室

public boolean updateRoomQuantity(String roomID, int amountOfRoomLeft){
    String sql = String.format("update room set roomAvailability =%d where roomID = '%s'", amountOfRoomLeft, roomID);
    try {
        stmt = conn.createStatement();
        stmt.executeUpdate(sql);
        return true;
    } catch (SQLException ex) {
        Logger.getLogger(RoomDA.class.getName()).log(Level.SEVERE, null, ex);
        JOptionPane.showMessageDialog(null, ex.getMessage(), "ERROR", JOptionPane.ERROR_MESSAGE);
        return false;
    }
}

預訂DA

public boolean addRecord(String booID, String booDate, String booTime, String roomID, double roomPrice, int duration, String memberID,
        String receptionistID, String checkinStatus, double totalRoomPrice, double totalPrice) {
    String sql = String.format("insert into booking values('%s','%s','%s','%s',%.2f,%d,'%s','%s','%s',%.2f,%.2f)", booID, booDate, booTime, roomID, roomPrice, duration, memberID, receptionistID, checkinStatus, totalRoomPrice, totalPrice);
    try {
        stmt = conn.createStatement();
        stmt.executeUpdate(sql);
        return true;
    } catch (SQLException ex) {
        Logger.getLogger(BookingDA.class.getName()).log(Level.SEVERE, null, ex);
        JOptionPane.showMessageDialog(null, ex.getMessage(), "ERROR", JOptionPane.ERROR_MESSAGE);
        return false;
    }
}

預訂面板添加按鈕

private void addBooking() {
    double total = 0.0;
    int roomQuantity= Integer.parseInt(jtfRoomQuantity.getText().trim());
    double price = Double.parseDouble(jtfRoomPrice.getText().trim());

    total = (roomQuantity* price);
    jtfTotalPrice.setText(String.valueOf(total));
    jtfTotalRoomPrice.setText(String.valueOf(total));
    if (!emptyFields()) {
        if (jcbAutoFillDate.isSelected()) {
            jbtFillInDate.doClick();
        }
        String booID = jtfBookingID.getText();
        String booDate = jtfBookingDate.getText();
        String booTime = jtfBookingTime.getText();
        String roomID = null;
        Room room = roomDA.getRecordByName(jtfAutoCompleteRoom.getText());
        double roomPrice = Double.parseDouble(jtfRoomPrice.getText());
        String memberID = null;
        Member member = memberDA.getRecordByName(jtfAutoCompleteMember.getText());
        String receptionistID = receptionistDA.getRecordByName(jcbAvailableReceptionist.getSelectedItem().toString()).getReceptionistID();
        String checkinStatus = jcbStatus.getSelectedItem().toString();
        double totalRoomPrice = Double.parseDouble(jtfTotalRoomPrice.getText());
        double totalPrice = Double.parseDouble(jtfTotalPrice.getText());

        memberID = member.getMemberID();
        roomID = room.getRoomID();

        if (bookingDA.addRecord(booID, booDate, booTime, roomID, roomPrice, duration, memberID, receptionistID, checkinStatus, totalRoomPrice, totalPrice)) {
            JOptionPane.showMessageDialog(null, "Successfully added");
            refreshTableContent();
            autoResizeTable();
            reset();
        }
    }
}

Answer 1

使用roomAvailability = roomAvailability -1

public boolean updateRoomQuantity(String roomID, int amountOfRoomLeft){
        String sql = String.format("update room set roomAvailability =roomAvailability-1 where roomID = '%s'", roomID);
        try {
            stmt = conn.createStatement();
            stmt.executeUpdate(sql);
            return true;
        } catch (SQLException ex) {
            Logger.getLogger(RoomDA.class.getName()).log(Level.SEVERE, null, ex);
            JOptionPane.showMessageDialog(null, ex.getMessage(), "ERROR", JOptionPane.ERROR_MESSAGE);
            return false;
        }
    }

在添加新記錄之前檢查可用性是否大於0.如果greter大於零則分配一個房間。 否則分配另一個房間。

Answer 2

在您的預訂DA中，您正在插入新的預訂，因此您還有更新剩余房間的房間DA。

roomDA.updateRoomQuantity(roomId, amountOfRoomLeft);

roomId存在於您的預訂中，唯一剩下的未知變量是amountOfRoomLeft。 因此，您應該編寫一個獲取amounttOfRoomLeft的新方法

就像是：

public int getRoomQuantity(String roomID){ String sql = String.format("select roomAvailability from room where roomID = '%s'", roomID); try { stmt = conn.createStatement(); ResultSet resultset = stmt.execute(sql); resultset.next(); return resultset.getInt(1); } catch (SQLException ex) { Logger.getLogger(RoomDA.class.getName()).log(Level.SEVERE, null, ex); JOptionPane.showMessageDialog(null, ex.getMessage(), "ERROR", JOptionPane.ERROR_MESSAGE); } }

你也應該自己做你的作業:)）