今天用java编写了一个租车系统,过程中主要遇到的两个问题:
1、输出数组信息问题:
在得到cars[]数组后,要生成租车信息表,目前有两种思路:一是用循环输出;二是用arrays.tostring()输出数组信息。
用tostring()方法输出数组输出……@……形式的哈希码地址,这里需要对tostring()方法进行重写,在数组涉及到的类中进行重写。
不过用第二种方法输出的其实还是一个数组,形式如图所示。那么问题来了——还有没有更好的输出方法呢?
2、父类方法不能访问子类成员变量:
本来在父类car中写好的getpersoncapacity()和getgoodcapacity()方法似乎不能访问子类中的personcapacity和goodcapacity 这两个成员变量,导致调用参数时始终为0;所以在各子类方法中又独立加上了前面两个方法,问题得以解决。
运行效果图:
代码如下:
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package rentcarsys;
/*
* 总共有三种车型:载人auto,载货van,载人载货pickup
* car 为这三种车型的父类
* 有4种属性:
* 编号 = number
* 品牌 = brand
* 租金/天 = fee
* 载人容量 = personcapacity
* 载货容量 = goodcapacity
*/
public class car {
int number;
string brand;
double fee;
int personcapacity;
double goodcapacity;
public car( int number, string brand, double fee){ //构造方法
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为载人汽车,除了car中的属性之外还有载人容量 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为载货汽车,除了car中的属性之外还有载货容量 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 + "吨" + "\n" ;
}
}
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package rentcarsys;
/*
* pickup为载人载货汽车,除了car中的属性之外还有载人容量 personcapacity,载货容量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 + "吨\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( "欢迎使用答答租车系统:" );
system.out.print( "您是否要租车?1、是 2、否(请输入1或2)" );
int input1 = input.nextint();
if (input1 == 1 ){
system.out.println( "下面是所有车的信息:" );
cars[ 0 ] = new auto( 1 , "奥迪a4" , 500.0 , 4 );
cars[ 1 ] = new auto( 2 , "马自达6" , 400.0 , 4 );
cars[ 2 ] = new pickup( 3 , "皮卡雪6" , 450.0 , 4 , 2 );
cars[ 3 ] = new auto( 4 , "金龙" , 800.0 , 20 );
cars[ 4 ] = new van( 5 , "松花江" , 400.0 , 4 );
cars[ 5 ] = new van( 6 , "依维柯" , 1000.0 , 20 );
system.out.println( "序号\t" + "汽车名称\t" + "租金\t\t" + "容量(载人/载货)" );
system.out.println(arrays.tostring(cars));
// for(int i = 0; i < cars.length; i++){
// system.out.println("编号:"+ (i+1) +" 品牌:"+ cars[i].getbrand()
// +" 租金:"+ cars[i].getfee() +"/天 载客量:"+ cars[i].getpersoncapacity()+"人"
// +" 载货量:"+ cars[i].getgoodcapacity()+"吨" );
// }
} else {
system.out.println( "谢谢使用,再见!" );
}
system.out.print( "请输入你要租几种车:" );
int rentnum = input.nextint();
//selected用来保存客户选中了什么车型,以及每种车型的辆数,与car数组是对应关系
int [] selected = new int [ 6 ];
for ( int i = 1 ; i <= rentnum; i++){
system.out.println( "请输入第" + i + "种车型的序号:" );
int nums = input.nextint() - 1 ;
system.out.println(cars[nums].getbrand() + "总共需要多少辆:" );
int num = input.nextint();
selected[nums] = num;
}
system.out.println( "请输入租车天数:" );
int daysnum = input.nextint();
system.out.println( "您的账单:--------------------------" );
double total = 0 ;
for ( int i = 0 ; i < cars.length; i++){
if (selected[i] != 0 ){
system.out.println(selected[i] + "辆" + cars[i].getbrand() +
" 总共载客量:" +selected[i]*cars[i].getpersoncapacity()+ "人" +
" 总共载货量:" +selected[i]*cars[i].getgoodcapacity()+ "吨" +
" " +daysnum+ "天单项费用:" +selected[i]*cars[i].getfee()*daysnum+ "元" );
total += selected[i]*cars[i].getfee()*daysnum;
}
}
system.out.println( "租车总费用:" + total + "元" + "\n" + "欢迎下次光临!------------------------" );
}
}
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以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持服务器之家。
原文链接:https://blog.csdn.net/chao2016/article/details/50532660