求教一个项目遇到的问题

package com.chy;

import java.util.Scanner;

public class IRecentCar {

Scanner input = new Scanner(System.in);

public void Show(){

System.out.println("欢迎来到答答租车系统");

System.out.println("请问您是否需要租车？"+"\t"+"是 (1) "+"否(0)");

int a =  input.nextInt();

if(a==1){

System.out.println("可租车辆如下：");

System.out.println("序号"+"\t"+"汽车名称"+"\t"+"\t"+"租金"+"\t"+"容量");

 this.Choose();

for(int i=1;i<cars.length;i++){

}

}

else if(a==0){

System.out.println("退出系统");

}

else{

System.out.println("您的输入有误，请重新输入");

this.Show();

}

}

public void Choose(){

Car[] cars = new Car[6];

Car c1 = new Iveco();

cars[1] = c1;

Car c2 = new Toyata();

cars[2] = c2;

Car c3 = new Mazda();

cars[3] = c3;

Car c4 = new RQ();

cars[4] = c4;

Car c5 = new StarLight();

cars[5] = c5;

Car c6 = new JieFang();

cars[6] = c6;

}

}

当我在Show（）方法的循环中使用cars的长度来遍历数组时为何会报错，这个方法我已经引用了，求各位大神指点