我想用集合装对象 但是为什么遍历不出来对象里的内容？

Question

        System.out.println("欢迎使用嗒嗒租车系统：");         System.out.println("您是否要租车：y是  否");         Scanner input = new Scanner (System.in);         String answer =input.nextLine();         char answer1 =answer.charAt(0);         if(answer1 == 'y'){             System.out.println("您可租车的类型和价目表");             System.out.println("序号  汽车名称  租金  容量");                          Car<String> benz = new Bus ("奔驰","400","1","4");             Car<String> jangling = new Bus ("江铃","300","1","15");             Car<String>sanling = new Truck("三菱","700","1","20");             Car<String> dayun = new Truck ("大运","1000","1","4");             Car<String> hanma = new Pickup ("悍马","400","1","10","4");             Test.pushCar().add(benz);             Test.pushCar().add(jangling );             Test.pushCar().add(sanling);             Test.pushCar().add(dayun);             Test.pushCar().add(hanma);             Iterator it = pushCar().iterator();             while(it.hasNext()){               Object obj = it.next();               System.out.println(obj.toString());             }         }else{             System.out.println("欢迎您再次光临");         }

Answer 1

[5.1.3]实战–介绍