Java - Setters 和继承 - 为什么我的 dailyFee 参数设置不正确？-6ren

Java - Setters 和继承 - 为什么我的 dailyFee 参数设置不正确？

转载作者：行者123 更新时间：2023-11-29 04:55:08

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大家晚上好!

作业越来越困惑了!同样，不是要求直接的答案，而是指向正确方向的指针，因此我们将不胜感激。

编辑 2:这里是有问题的练习，如果它有助于清除任何东西:

我想知道如何使用 UseCarRental.java 文件在 CarRental.java 文件中设置 dailyFee 变量。 CarRental.java 中的 if 语句似乎无法正常工作(输入大小不会设置 dailyFee 变量)。此外，如果我为尺寸输入“l”，它不会提示 LuxuryCarRental.java。这是代码:

汽车租赁.java

import javax.swing.JOptionPane;

public class CarRental 
{
private String name;
private String zipCode;
private String size;
private double dailyFee;
private int rentalDays;
private double totalFee;

public CarRental(String name, String zipCode, String size, double dailyFee, int rentalDays, double totalFee)
{
    this.name = name;
    this.zipCode = zipCode;
    this.size = size;
    if (size == "e")
    {
        this.dailyFee = 29.99;
    }
    else if (size == "m")
    {
        this.dailyFee = 38.99;
    }
    else if (size == "f")
    {
        this.dailyFee = 43.50;
    }
    this.dailyFee = dailyFee;
    this.rentalDays = rentalDays;
    totalFee = dailyFee * rentalDays;
}

public CarRental(){}

public void display()
{
    JOptionPane.showMessageDialog(null, "Luxury car for " + name + " from zip code " + zipCode + "\n"
            + "Type = " + size + "\n"
            + "Daily Fee = " + dailyFee + "\n"
            + "Days = " + rentalDays + "\n"
            + "Your rental is $" + totalFee);
}

//includes getters and setters but I didn't include them in this post

LuxuryCarRental.java

import javax.swing.JOptionPane;

public class LuxuryCarRental extends CarRental
{
    public LuxuryCarRental(String name, String zipCode, String size, double dailyFee, int rentalDays, double totalFee, String includeChauffeur)
    {
        super(name, zipCode, size, dailyFee, rentalDays, totalFee);
        if (size == "l")
        {
            dailyFee = 79.99;
            includeChauffeur = JOptionPane.showInputDialog(null, "Include chauffeur? Y/N");
            if (includeChauffeur == "Y")
            {
                totalFee = totalFee + 200;
            }
        }
    }
}

UseCarRental.java(不完整)

import javax.swing.JOptionPane;

public class UseCarRental 
{

    public static void main(String[] args) 
    {
        CarRental userInfo = new CarRental();
        userInfo.setName(JOptionPane.showInputDialog("Enter name"));
        userInfo.setZipCode(JOptionPane.showInputDialog("Enter zip code"));
        userInfo.setSize(JOptionPane.showInputDialog("Enter type of car" + "\n" + "e - economy" + "\n" + "m - midsize" + "\n" + "f - full" + "\n" + "l - luxury"));
        userInfo.setRentalDays(Integer.parseInt(JOptionPane.showInputDialog("Enter days to rent")));


        System.out.println(userInfo.getDailyFee());

        userInfo.display();

    }
}