今天用java編寫了一個租車系統(tǒng)，過程中主要遇到的兩個問題：
1、輸出數(shù)組信息問題：
在得到cars[]數(shù)組后，要生成租車信息表，目前有兩種思路：一是用循環(huán)輸出；二是用arrays.tostring()輸出數(shù)組信息。
用tostring()方法輸出數(shù)組輸出……@……形式的哈希碼地址，這里需要對tostring()方法進行重寫，在數(shù)組涉及到的類中進行重寫。
不過用第二種方法輸出的其實還是一個數(shù)組，形式如圖所示。那么問題來了——還有沒有更好的輸出方法呢？
2、父類方法不能訪問子類成員變量：
本來在父類car中寫好的getpersoncapacity()和getgoodcapacity()方法似乎不能訪問子類中的personcapacity和goodcapacity 這兩個成員變量，導致調(diào)用參數(shù)時始終為0；所以在各子類方法中又獨立加上了前面兩個方法，問題得以解決。
運行效果圖：
代碼如下：
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package rentcarsys;/* * 總共有三種車型：載人auto，載貨van，載人載貨pickup * car 為這三種車型的父類 * 有4種屬性： * 編號 = number * 品牌 = brand * 租金/天 = fee * 載人容量 = personcapacity * 載貨容量 = goodcapacity */public class car { int number; string brand; double fee; int personcapacity; double goodcapacity; public car(int number, string brand, double fee){ //構(gòu)造方法 this.number = number; this.brand = brand; this.fee = fee; } public int getnumber(){ return number; } public string getbrand(){ return brand; } public double getfee(){ return fee; } public int getpersoncapacity(){ return personcapacity; } public double getgoodcapacity(){ return goodcapacity; } } |
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package rentcarsys;/* * auto為載人汽車，除了car中的屬性之外還有載人容量 personcapacity */public class auto extends car{ private int personcapacity; public auto(int number, string brand, double fee, int personcapacity) { super(number, brand, fee); this.personcapacity = personcapacity; } public int getpersoncapacity() { return personcapacity; } @override public string tostring() { return number + "\t" + brand + "\t" + fee + "元/天\t" + personcapacity + "人\n"; } } |
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package rentcarsys;/* * van為載貨汽車，除了car中的屬性之外還有載貨容量 goodcapacity */public class van extends car{ private double goodcapacity; public van(int number, string brand, double fee, double goodcapacity) { super(number, brand, fee); this.goodcapacity = goodcapacity; } public double getgoodcapacity(){ return goodcapacity; } public string tostring() { return number + "\t" + brand + "\t" + fee + "元/天\t" + goodcapacity + "噸" + "\n"; } } |
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package rentcarsys;/* * pickup為載人載貨汽車，除了car中的屬性之外還有載人容量 personcapacity,載貨容量goodcapacity */public class pickup extends car{ private int personcapacity; private double goodcapacity; public pickup(int number, string brand, double fee, int personcapacity, double goodcapacity) { super(number, brand, fee); this.personcapacity = personcapacity; this.goodcapacity = goodcapacity; } public int getpersoncapacity() { return personcapacity; } public double getgoodcapacity(){ return goodcapacity; } @override public string tostring() { return number + "\t" + brand + "\t" + fee + "元/天\t" + personcapacity + "人\t" + goodcapacity + "噸\n"; }} |
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package rentcarsys; import java.util.arrays;import java.util.scanner; public class login { public static void main(string[] args){ scanner input = new scanner(system.in); car[] cars = new car[6]; system.out.print("歡迎使用答答租車系統(tǒng)："); system.out.print("您是否要租車？1、是 2、否（請輸入1或2）"); int input1 = input.nextint(); if (input1 == 1){ system.out.println("下面是所有車的信息："); cars[0] = new auto(1, "奧迪a4", 500.0, 4); cars[1] = new auto(2, "馬自達6", 400.0, 4); cars[2] = new pickup(3, "皮卡雪6", 450.0, 4, 2); cars[3] = new auto(4, "金龍", 800.0, 20); cars[4] = new van(5, "松花江", 400.0, 4); cars[5] = new van(6, "依維柯", 1000.0, 20); system.out.println("序號\t" + "汽車名稱\t" + "租金\t\t" + "容量(載人/載貨)"); system.out.println(arrays.tostring(cars));// for(int i = 0; i < cars.length; i++){// system.out.println("編號:"+ (i+1) +" 品牌:"+ cars[i].getbrand() // +" 租金:"+ cars[i].getfee() +"/天 載客量:"+ cars[i].getpersoncapacity()+"人"// +" 載貨量:"+ cars[i].getgoodcapacity()+"噸" );// } }else{ system.out.println("謝謝使用，再見！"); } system.out.print("請輸入你要租幾種車："); int rentnum = input.nextint(); //selected用來保存客戶選中了什么車型，以及每種車型的輛數(shù)，與car數(shù)組是對應關系 int[] selected = new int[6]; for (int i = 1; i <= rentnum; i++){ system.out.println("請輸入第" + i + "種車型的序號：" ); int nums = input.nextint() - 1; system.out.println(cars[nums].getbrand() +"總共需要多少輛："); int num = input.nextint(); selected[nums] = num; } system.out.println("請輸入租車天數(shù)："); int daysnum = input.nextint(); system.out.println("您的賬單：--------------------------"); double total = 0; for (int i = 0; i < cars.length; i++){ if (selected[i] !=0 ){ system.out.println(selected[i] + "輛" + cars[i].getbrand() + " 總共載客量:"+selected[i]*cars[i].getpersoncapacity()+"人"+ " 總共載貨量:"+selected[i]*cars[i].getgoodcapacity()+"噸"+ " "+daysnum+"天單項費用:"+selected[i]*cars[i].getfee()*daysnum+"元"); total += selected[i]*cars[i].getfee()*daysnum; } } system.out.println("租車總費用：" + total + "元" + "\n" + "歡迎下次光臨！------------------------"); }} |
以上就是本文的全部內(nèi)容，希望對大家的學習有所幫助，也希望大家多多支持服務器之家。
原文鏈接：https://blog.csdn.net/chao2016/article/details/50532660
