答答租车（从零基础第一季学到第二季，我写出的水平就这样了，欢迎纠正）

主程序

public class Text {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    Car type[]={new Bus("奥迪A4", 500, 4),new Bus("马自达", 400, 4),
            new Bus("金龙", 800, 20), new PickUp("皮卡雪", 450, 4, 2),
            new Trunk("松花江", 400, 4),new Trunk("依维柯", 1000, 20)};
    System.out.println("欢迎进入租车系统");
    System.out.println("租车请按1，退出请按0");
    //@SuppressWarnings("resource")
    int select=new Scanner(System.in).nextInt();
    if(select==1){
        System.out.println("下面是可租车的信息");
        System.out.println("*****************************************");
        System.out.println("序号\t车名\t每日租金\t容量");
        for(int i=0;i<type.length;i++){
            System.out.println((i+1)+"\t"+type[i]);
        }
        System.out.println("*****************************************");
        System.out.println("您要租几种车?");
        int kinds=new Scanner(System.in).nextInt();
        if(kinds>6){
            System.out.println("本系统只有6类车可供选择，请重新输入6或6以下的数字");
            int kinds2=new Scanner(System.in).nextInt();
            kinds=kinds2;
        }
        System.out.println("您需要租多少天?");
        int days=new Scanner(System.in).nextInt();
        System.out.println("请输入要租车的序号");
        int xuhao[]=new int[kinds];
        int money=0,numPer=0,numGoo=0;
        for(int a=0;a<xuhao.length;a++){
            xuhao[a]=new Scanner(System.in).nextInt();
            if(xuhao[a]==1){
                money=money+500*days;
                numPer=numPer+4;
                numGoo=numGoo+0;
            }else if(xuhao[a]==2){
                money=money+400*days;
                numPer=numPer+4;
                numGoo=numGoo+0;
            }else if(xuhao[a]==3){
                money=money+800*days;
                numPer=numPer+20;
                numGoo=numGoo+0;
            }else if(xuhao[a]==4){
                money=money+450*days;
                numPer=numPer+4;
                numGoo=numGoo+2;
            }else if(xuhao[a]==5){
                money=money+400*days;
                numPer=numPer+0;
                numGoo=numGoo+4;
            }else if(xuhao[a]==6){
                money=money+1000*days;
                numPer=numPer+0;
                numGoo=numGoo+20;
            }else{
                System.out.println("您输入错误，请重新输入");
                xuhao[a]=new Scanner(System.in).nextInt();
            }
        }
        System.out.println("-----------------------------------------------------------------------------");
        System.out.println("您的订单如下：");
        System.out.println("车名\t每日租金\t容量\t\t总容量\t\t\t总金额");
        for(int b=0;b<kinds;b++){
            if(b==(kinds-1)){
                System.out.println(type[xuhao[b]-1]+"\t\t"+"总载人:"+numPer+"人   "+"总载物："+numGoo+"吨"+"\t"+money+"元");
                break;
            }
            System.out.println(type[xuhao[b]-1]);
        }
        System.out.println("-----------------------------------------------------------------------------");
        System.out.println("感谢您的使用，期待您的下次光临！！！");
    }else if(select==0){
        System.out.println("期待您的下次使用");
        System.exit(0);
    }else{
        System.out.println("您的输入有误，请仔细查看再次输入");
        System.out.println();
        System.out.println();
        main(args);
    }
}

}

抽象父类

public abstract class Car {
private String name;
private int price;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
}
@Override
public String toString() {
return name+"\t"+price+"\t";
}

}

两接口

public interface IGoods {
public int getGoods();
public void setGoods(int goods);
}

public interface IPerson {
public int getPerson();
public void setPerson(int person);
}

各子类
public class Bus extends Car implements IPerson{
private int person;
@Override
public int getPerson() {
// TODO Auto-generated method stub
return person;
}

@Override
public void setPerson(int person) {
    // TODO Auto-generated method stub
    this.person=person;
}
public Bus(String name,int price,int person){
    this.setName(name);
    this.setPrice(price);
    this.setPerson(person);
}

@Override
public String toString() {
    return super.toString()+"载人:"+this.getPerson()+"人";
}

}

public class PickUp extends Car implements IPerson,IGoods{
private int person;
private int goods;
@Override
public int getGoods() {
// TODO Auto-generated method stub
return goods;
}
@Override
public void setGoods(int goods) {
// TODO Auto-generated method stub
this.goods=goods;
}
@Override
public int getPerson() {
// TODO Auto-generated method stub
return person;
}
@Override
public void setPerson(int person) {
// TODO Auto-generated method stub
this.person=person;
}
public PickUp(String name,int price,int person,int goods){
this.setName(name);
this.setPrice(price);
this.setPerson(person);
this.setGoods(goods);
}
@Override
public String toString() {
return super.toString()+"载人:"+this.getPerson()+"人"+" "+"载物:"+this.getGoods()+"吨";
}

}

public class Trunk extends Car implements IGoods{
private int goods;
@Override
public int getGoods() {
// TODO Auto-generated method stub
return goods;
}

@Override
public void setGoods(int goods) {
    // TODO Auto-generated method stub
    this.goods=goods;
}
public Trunk(String name,int price,int goods){
    this.setName(name);
    this.setPrice(price);
    this.setGoods(goods);
}

@Override
public String toString() {
    return super.toString()+"载物:"+this.getGoods()+"吨";
}

}