package study;

import java.util.HashSet;

import java.util.Set;

class BookInfo {

String bookName;

String auther;

double price;

public BookInfo(String bookName,String auther,double price) {

this.bookName=bookName;

this.auther=bookName;

this.price=price;

}

public double getPrice() {

return price;

}

public String toString() {

return bookName+auther+price;

}

}

public class ShopCar {

HashSet<BookInfo> hasSetBook=new HashSet<>();

BookInfo[] books= {new BookInfo("java入门", "明日", 69.6), 

           new BookInfo("javaweb", "明日", 59.8),

           new BookInfo("java精通", "明日", 69.6)};

hass

}

1. 动手敲。

2. 在方法里写逻辑代码。