计算totalCost

Question

以下是我正在上课的代码...我需要知道如何正确编写此产品的totalCost代码，我不能为我的生活找出如何正确地执行此操作。每件产品的价格是1美元，我也需要计算7％的销售税。帮助！

导入javax.swing.JOptionPane;

/ **  * @author bary  * / 公共课CocaCola1 {

    public static void main(String[] args) 
    {


        String openingMsg = "*** Welcome to CocaCola Online Ordering System ***\n" 
                   + "Do yourself a favor and order some Cola... NOW!";
        JOptionPane.showMessageDialog(null, openingMsg);
        System.out.println(0);

        String name = getUserInput("What is your name?");
        System.out.println(name);

        String returnCustomer = getUserInput("Are you a returning customer? (yes/no)");
        System.out.println(returnCustomer);

        String orderType = getUserInput("Would you like to purchase Dasani, Coke, Diet Coke, or Cherry Coke?");
        System.out.println(orderType);

        String orderAmount = getUserInput("How many units would you like to purchase?");
        System.out.println(orderAmount);
        Integer.parseInt(orderAmount);
        // each unit costs $1.00 so orderAmount is equal to cost per unit

        double salesTax = 0.7;


        // create and display output string
                String outputMsg
                = "Hello " +  name + ".\n\n" +
                    "Your return customer status is " + returnCustomer + ".\n" +
                    "You ordered " + orderAmount + 
                    " units of " + orderType + ".\n" +
                    "Your total cost is $" + orderAmount + salesTax + ".\n" +
                    "Thank you for visiting CocaCola" + ".\n\n" +
                    "Your order will be proccessed ASAP.\n";
                JOptionPane.showMessageDialog(null, outputMsg);
    }



    private static String getUserInput(String prompt)
    {
        int failCount = 0;
        do
        {
            String answer = JOptionPane.showInputDialog(prompt);
            if (answer == null)
            {
                System.exit(0);
            }

            answer = answer.trim();
            if (answer.isEmpty())
            {
                JOptionPane.showMessageDialog(null, "You must provide a non-blank answer");
                failCount = failCount + 1;
            } else
            {
                return answer;
            }
        } while (failCount < 3);

        JOptionPane.showMessageDialog(null, "You failed three times to provide input... Try again later!");
        System.exit(0);
        return null; // means nothing, as I just exited on the prior line, but need it to compile


} // end main()

} //结束课CocaCola1

Answer 1

orderAmount + salesTax仅在销售税为静态时才会出现。您需要将orderAmount乘以销售税并添加salestax

ex：orderAmount * salesTax + prderAmount

或将salesTax设置为1.7即可 orderAmount *销售税