第九周作业
public class Book { private Integer id; private String name; private Integer price; public Book(Integer id, String name, Integer price) { super(); this.id = id; this.name = name; this.price = price; } public Integer getId() { return id; } public void setId(Integer id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public Integer getPrice() { return price; } public void setPrice(Integer price) { this.price = price; } public Book(){ super(); } public String toString() { return "book [id=" + id + ", name=" + name + ", price=" + price + "]"; } }
import java.util.List; import java.util.ArrayList; import java.util.Scanner; public class test { static java.util.List<Book> list=new ArrayList<Book>(); static{ Book book1=new Book(1,"软件测试",33); Book book2=new Book(2,"Java",35); Book book3=new Book(3,"网络安全测试",30); list.add(book1); list.add(book2); list.add(book3); } public static void main(String[] args) { while(true){ System.out.println("1.添加"); System.out.println("2.删除"); System.out.println("3.修改"); System.out.println("4.查询"); System.out.println("5.退出"); System.out.println("请选择"); Scanner scanner=new Scanner(System.in); int a=scanner.nextInt(); switch (a) { case 1: add(); break; case 2: del(); break; case 3: change(); break; case 4: search(); break; case 5: System.out.println("退出成功"); return; } } } private static void search(){ for(Book book4:list){ System.out.println(book4); } } private static void change(){ System.out.println("请输入需要修改的图书编号"); int update=new Scanner(System.in).nextInt(); for(Book book:list){ if(update==book.getId()){ System.err.println("请输入书名"); String name1=new Scanner(System.in).next(); System.err.println("请输入价格"); int price1=new Scanner(System.in).nextInt(); book.setName(name1); book.setPrice(price1); System.out.println("修改成功"); } } } private static void del(){ System.out.println("请输入删除的图书编号"); int id=new Scanner(System.in).nextInt(); try{ for(Book book:list){ if(list.size()!=0){ if(id==book.getId()){ list.remove(book); System.out.println("删除成功"); } } } }catch(Exception e){ } } private static void add(){ Scanner scanner=new Scanner(System.in); System.err.println("请输入编号"); int idd=scanner.nextInt(); System.err.println("请输入书名"); String name2=scanner.next(); System.err.println("请输入价格"); int price2=scanner.nextInt(); Book book=new Book(idd,name2,price2); list.add(book); System.out.println("添加成功"); } }
2.上题的类,在一个JSP页面中,创建一个集合,里面放3个图书,集合循环遍历显示在页面上。
<%@page import="qmt.Book" %> <%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <% List<Book> list =new ArrayList<Book>(); Book book1 =new Book(1,"大学英语",25); list.add(book1); Book book2 =new Book(2,"计算机组成原理",20); list.add(book2); Book book3 =new Book(3,"线性代数",27); list.add(book3); for (Book book4 : list) { out.print(book4+"<br>"); } %> <body> </body> </html>
3.在MySQL中创建Book表,里面id,name,price,
用命令实现,
create database myBook; use myBook; create table book( id int comment '书籍编号', bookName varchar(10) comment '书名', bookPrice double(6,2) comment '书籍价格' )comment '书籍表'; desc book; insert into book values (1,'考研真相',45); insert into book values (2,'毛概',38); insert into book values (3,'概率',22); insert into book values (4,'安卓',34); select * from book;
根据名称删除图书
delete from book where bookName ='毛概';
把所有名称是“安”开头的图书删除
lete from book where bookName like '安%';
删除全部图书,
delete from book;
把20元以上的图书价格都修改为18.8,查看全部图书,
update book set bookPrice=18.8 where bookPrice>20;
查看价格高于10块钱的全部图书
select * from book where bookPrice>10;