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package?com.stduy;
import??java.util.Scanner;
//從功能上分，總共分為三種，載人汽車，載貨汽車，既載人又載貨。
//對應(yīng)Bus,Truck,PickUp
public?class?Initail?{
????private?static?int?choice;
????static?Scanner??input?=?new?Scanner(System.in);
????private?static?Car[]?cars=?new?Car[]{
????????????new?Bus("巴士車",500,10),
????????????new?Truck("卡車",300,5),
????????????new?PickUp("皮卡車",?600,?6,?7)
????};
????public?static?void?main(String[]?args)?{
????????System.out.println("歡迎使用租車系統(tǒng)");
????????//Java不需要先聲明，和C不同。
????????//?原因是：類加載編譯時(shí)就把程序的入口初始化了，執(zhí)行時(shí)是JAVA虛擬機(jī)所識別的特定字節(jié)碼，
????????//?C卻是處理器可直接執(zhí)行的二進(jìn)制指令，編譯的原理不一樣，語言獨(dú)特的特性與運(yùn)行環(huán)境不一樣。
????????IsNeed();//判斷是否要租車
????????if(choice==1){
????????????DisplayList();?//顯示可租車清單
????????????int?num=RentNum();//獲取租車的種類數(shù)
????????????RentList[]?rentLists=new?RentList[num];//填寫出租信息表
????????????rentLists=RentForm(num);
????????????Pay(rentLists,cars);//生成賬單
????????}
????}

????public?static?void?IsNeed()?{
????????System.out.println("您是否要租車：1是?0否");
????????choice?=?input.nextInt();
????????if?(choice?==?0)?{
????????????System.out.println("感謝使用，再見");
????????}?else?if?(choice?!=?1)?{
????????????System.out.println("輸入錯(cuò)誤，請重新輸入");
????????}
????}

????//關(guān)鍵字instanceof,測試一個(gè)對象是否為一個(gè)類的實(shí)例
????public?static?void?DisplayList(){
????????System.out.println("您可租車的型號和價(jià)格表");
????????for(int?i?=?0;?i<cars.length;?i++){
????????????????if(cars[i]?instanceof?Bus){
????????????????????Bus?car=(Bus)cars[i];//強(qiáng)制類型轉(zhuǎn)換
????????????????????System.out.println((i?+?1)?+?"?"?+?car.name+"?"+car.rent+"元/天"+"?"+"核載"+car.person+"人");
????????????????}
????????????????else?if(cars[i]?instanceof?Truck){
????????????????????Truck?car=(Truck)cars[i];
????????????????????System.out.println((i?+?1)?+?"?"?+?car.name+"?"+car.rent+"元/天"+"?"+"核載"+car.goods+"噸");
????????????????}
????????????????else?if(cars[i]?instanceof?PickUp){
????????????????????PickUp?car=(PickUp)cars[i];
????????????????????System.out.println((i?+?1)?+?"?"?+?car.name+"?"+car.rent+"元/天"+"?"+"核載"+car.person+"人"+"?"+"核載"+car.goods+"噸");
????????????????}
????????????}
????}
????//以下為輸入部分
????//獲取租車數(shù)量
????private?static?int?RentNum(){
????????System.out.println("請輸入您要總共租車的種類數(shù):");
????????int?RentNum=input.nextInt();
????????return?RentNum;
????}
????//租車信息表
????private??static??RentList[]?RentForm??(int?num){
????????//租車信息對象數(shù)組
????????RentList[]??rentLists=new?RentList[num];

????????for(int?i=0;i<num;i++){
????????????//型號
????????????System.out.println("請輸入租的第"+(i+1)+"類車的信息");
????????????System.out.print("型號：");
????????????int?Model=input.nextInt();
????????????//該型號的數(shù)量
????????????System.out.print("數(shù)量：");
????????????int?Num=input.nextInt();
????????????//該型號租的天數(shù)
????????????System.out.print("天數(shù)：");
????????????int?Day=input.nextInt();
????????????//將信息存入對象數(shù)組
????????????rentLists[i]=new?RentList();//這步不能掉
????????????rentLists[i].setModel(Model);
????????????rentLists[i].setNum(Num);
????????????rentLists[i].setDay(Day);
????????}
????????return?rentLists;
????}
????//生成賬單
????private?static?void?Pay(RentList[]?rentLists,Car[]?cars){
????????//打印清單
????????System.out.println("************結(jié)算清單*************");
????????System.out.println("型號????????數(shù)量????????租用天數(shù)");
????????double?SumMoney=0;
????????for(int?i=0;i<rentLists.length;i++){
????????????//用get方法獲得數(shù)據(jù)，更好的封裝RentList類
????????????int?Model=rentLists[i].getModel();
????????????int?Num=rentLists[i].getNum();
????????????int?Day=rentLists[i].getDay();
????????????double?Rent=cars[i].getRent();
????????????SumMoney+=Num*Day*Rent;
????????????System.out.println(Model+"????????????"+Num+"????????????"+Day);
????????}
????????System.out.println("您總共要支付"+SumMoney+"元");
????}
????//這里也可以通過重寫toString方法輸出
????//toString方法為Object類中的方法，返回對象的哈希碼,即地址
????//不重寫toString方法，則直接輸入對象是輸出該對象的地址
}

//父類，車

package?com.stduy;
//車
public?class?Car?{
????protected???String?name;//車型,protect方便繼承
????protected???double?rent;//租金
????public?Car(String?name,double?rent){//用構(gòu)造方法初始化
????????this.name=name;
????????this.rent=rent;
????}

????public?String?getName()?{
????????return?name;
????}
????public?double?getRent()?{
????????return?rent;
????}

????public?void?setName(String?name)?{
????????this.name?=?name;
????}

????public?void?setRent(double?rent)?{
????????this.rent?=?rent;
????}
}

//載人車

package?com.stduy;

//Bus,載人汽車
public?class?Bus?extends?Car?{
????//子類的構(gòu)造過程當(dāng)中必須調(diào)用其父類的構(gòu)造方法
????//無參時(shí)隱式執(zhí)行super(),子類如果沒有顯式調(diào)用，父類又沒有無參的構(gòu)造方法則編譯出錯(cuò)
????//java里一個(gè)類可以有多個(gè)構(gòu)造方法
????//super關(guān)鍵字必須放在第一行
????protected?int?person;//載人數(shù)
????//構(gòu)造方法
????public?Bus(String?name,?double?rent,int?person)?{
????????super(name,?rent);
????????this.person=person;
????}

????public?int?getPerson()?{
????????return?person;
????}

????public?void?setPerson(int?person)?{
????????this.person?=?person;
????}
}

//載貨車

package?com.stduy;
//貨車
public?class?Truck?extends?Car{

????protected?double?goods;//貨物
????//構(gòu)造方法
????public?Truck(String?name,?double?rent,?double?goods)?{
????????super(name,?rent);
????????this.goods=goods;
????}

????public?double?getGoods()?{
????????return?goods;
????}

????public?void?setGoods(double?goods)?{
????????this.goods?=?goods;
????}
}

//既載貨又載人

package?com.stduy;

//皮卡，既能載貨又能載人
public?class?PickUp?extends?Car?{

????protected?int?person;//載人數(shù)
????protected?double?goods;//貨物
????//構(gòu)造方法
????public?PickUp(String?name,?double?rent,int?person,double?goods)?{
????????super(name,?rent);
????????this.person=person;
????????this.goods=goods;
????}

????public?int?getPerson()?{
????????return?person;
????}

????public?double?getGoods()?{
????????return?goods;
????}

????public?void?setPerson(int?person)?{
????????this.person?=?person;
????}

????public?void?setGoods(double?goods)?{
????????this.goods?=?goods;
????}
}

//租車信息表

package?com.stduy;
//租車信息表
public?class?RentList?{
????private??int?Model;//型號
????private??int?Num;//要租該型號的數(shù)量
????private??int?Day;//要租該型號的天數(shù)

????public?int?getModel()?{
????????return?Model;
????}

????public?int?getNum()?{
????????return?Num;
????}

????public?int?getDay()?{
????????return?Day;
????}

????public?void?setModel(int?model)?{
????????Model?=?model;
????}

????public?void?setNum(int?num)?{
????????Num?=?num;
????}

????public?void?setDay(int?day)?{
????????Day?=?day;
????}
}

遠(yuǎn)赴山河萬里

2020-03-17

源自：Java入門第二季升級版 12-1

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6 回答

weixin_慕運(yùn)維0427676
2020-04-05

膜拜大佬，大佬學(xué)習(xí)多久了

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#1

遠(yuǎn)赴山河萬里提問者

兩天...

2020-04-15 回復(fù) 有任何疑惑可以回復(fù)我~

慕圣大越越
2020-03-19

為啥我自己就寫不出來呢？?難過

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慕圣大越越
2020-03-19

大神厲害！我自己按照你的這個(gè)寫了一遍，發(fā)現(xiàn)了一個(gè)bug；如果只租兩種或一種車，結(jié)果就會(huì)出現(xiàn)錯(cuò)誤。建議把double Rent = cars[i].getRent();改成double Rent = cars[Model-1].getRent();

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#1

遠(yuǎn)赴山河萬里提問者

對，這里是有問題，感謝指正，我也是才學(xué)java，寫C的習(xí)慣總是改不掉，所以才備注知識點(diǎn)。

2020-03-20 回復(fù) 有任何疑惑可以回復(fù)我~

#2

遠(yuǎn)赴山河萬里提問者

這里的算法其實(shí)可以有很多種實(shí)現(xiàn)，主要是習(xí)慣語法，感謝指正

2020-03-20 回復(fù) 有任何疑惑可以回復(fù)我~

慕容7252138
2020-03-18

你好，想問個(gè)問題，你的Pay方法中，rentList 和 cars的型號沒有判斷是否匹配，如果用戶不按照順序選擇車的類型，車的租金應(yīng)該會(huì)匹配有誤吧

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#1

遠(yuǎn)赴山河萬里提問者

對，這里是有問題，我寫完也發(fā)覺了，但是后來我又想實(shí)現(xiàn)刪除等功能，我就用鏈表實(shí)現(xiàn)了，這個(gè)就被推翻了，所以就沒改。望見諒，只是提供一個(gè)框架，里面的數(shù)據(jù)結(jié)構(gòu)可以自己設(shè)計(jì)，才疏學(xué)淺，抱歉。

2020-03-19 回復(fù) 有任何疑惑可以回復(fù)我~

#2

慕圣大越越

把double Rent = cars[i].getRent();改成double Rent = cars[Model-1].getRent();就匹配嘍

2020-03-19 回復(fù) 有任何疑惑可以回復(fù)我~