如何在Java Swing中的将文本打印到热敏打印机的参数中设置发票

Question

我正在尝试在热敏打印机的参数打印文本中设置发票，但它显示值为空。请帮助我任何人如何以字符串参数形式生成发票作为文本。
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    PrinterService printerService = new PrinterService();

    System.out.println(printerService.getPrinters());

    //print some stuff. Change the printer name to your thermal printer name.

    printerService.printString("POSIFLEX PP6900 PRINTER", "   ****POS System**** \n"
            + "Date: "+Date+"     Time: "+Time+"\n"
            + "Receipt Number: "+ReceiptNumber+"\n"
            + "---------------------------------\n"
            + "Name          Qty    Rate     Amt\n"
            + "---------------------------------\n"
            + " "+ GetProductName(prodId)+ " "+quan+"  * "+totalamt+"  " +price+"\n"
            + "---------------------------------\n"
            + "Subtotal: "+GetCartAmount()+"\n"
            + "Tax: "+String.valueOf(tax)+"\n"
            + "Bonus: "+GetDiscountAmount(ReceiptNumber)+"\n"
            + "Payment: "+String.valueOf(total)+"\n"
            + "---------------------------------\n"
            + "------Served by: "+ItemSoldB+"-----\n"
    );
    // cut that paper!
    byte[] cutP = new byte[] { 0x1d, 'V', 1 };

    printerService.printBytes("POSIFLEX PP6900 PRINTER", cutP);`