1.做一个图书类Book id,name,price ,get,set访问器,构造方法2个,1个无参,1个有参做一个测试类,在main中创建3个图书对象,放到list集合中。做一个菜单,可以添加,删除,修改,查询
package BookPackage;

public class Book {
    int id;
    String name;
    double price;
    
    
    public Book() {
        super();
    }
    public Book(int id, String name, double price) {
        super();
        this.id = id;
        this.name = name;
        this.price = price;
    }
    
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public double getPrice() {
        return price;
    }
    public void setPrice(double price) {
        this.price = price;
    }
    
    
}
package BookPackage;

import java.util.ArrayList;
import java.util.Scanner;

public class main {

    static ArrayList<Book> booklist=new ArrayList<Book>();
    static Scanner sc=new Scanner(System.in);
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Book book1=new Book(100,"三国演义",20);
        Book book2=new Book(200,"红楼梦",30);
        Book book3=new Book(300,"水浒传",10);
        
        booklist.add(book1);
        booklist.add(book2);
        booklist.add(book3);
        
        for (int i = 0; i <booklist.size(); i++) {
            Book b= booklist.get(i);
            System.out.println("图书编号:"+b.getId()+",图书名称:"+b.getName()+",图书价格"+b.getPrice());
        }
        System.out.println("===========================");
        shouye();

    }
    
    public static void shouye() {
        System.out.println("请输入你需要的选项:");
        System.out.println("1.添加图书");
        System.out.println("2.删除图书");
        System.out.println("3.修改图书");
        System.out.println("4.查询图书");
        System.out.println("===========================");
        caidan();
    }
    
    public static void caidan() {
        int num=sc.nextInt();
        switch (num) {
        case 1:
            tianjia();
            break;
        case 2:
            shanchu();
            break;
        case 3:
            xiugai();
            break;
        case 4:
            chaxun();
            break;
        default:
            break;
        }
    }

    private static void chaxun() {
        // TODO Auto-generated method stub
        System.out.println("请输入要查询图书名称:");
        String bookname=sc.next();
        for (int i = 0; i < booklist.size(); i++) {
            if(booklist.get(i).getName().equals(bookname)){
                System.out.println("===========================");
                Book b= booklist.get(i);
                System.out.println("图书编号:"+b.getId()+",图书名称:"+b.getName()+",图书价格"+b.getPrice());
            }
        }
    }

    private static void xiugai() {
        // 修改图书信息
        System.out.println("请输入要修改的图书id:");
        int bookid=sc.nextInt();
        for (int i = 0; i < booklist.size(); i++) {
            if(booklist.get(i).getId()==bookid){
                booklist.remove(i);
                System.out.println("请输入新的图书编号:");
                int id=sc.nextInt();
                System.out.println("请输入新的图书名称:");
                String name=sc.next();
                System.out.println("请输入新的图书价格:");
                double price=sc.nextDouble();
                Book newbook=new Book(id,name,price);
                booklist.add(newbook);
            }
        }
        System.out.println("图书信息修改完成!");
        System.out.println("===========================");
        mulu();
        shouye();
    }

    private static void shanchu() {
        // 删除图书
        System.out.println("请输入要删除的图书名称:");
        String bookname=sc.next();
        for (int i = 0; i < booklist.size(); i++) {
            if(booklist.get(i).getName().equals(bookname)){
                booklist.remove(i);
            }
        }
        System.out.println("删除成功!");
        System.out.println("===========================");
        mulu();
        shouye();
    }

    private static void tianjia() {
        //添加图书
        System.out.println("请输入图书编号:");
        int id=sc.nextInt();
        System.out.println("请输入图书名称:");
        String name=sc.next();
        System.out.println("请输入图书价格:");
        double price=sc.nextDouble();
        Book newbook=new Book(id,name,price);
        booklist.add(newbook);
        System.out.println("新图书添加完成!");
        System.out.println("===========================");
        mulu();
        shouye();
    }

    private static void mulu() {
        // 更新后图书目录
        for (int i = 0; i <booklist.size(); i++) {
            Book b= booklist.get(i);
            System.out.println("图书编号:"+b.getId()+",图书名称:"+b.getName()+",图书价格"+b.getPrice());
        }
        System.out.println("===========================");
    }
    

}

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="book.Book"%>
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head></head>
   
  <body>
  图书:<br>
<%
 
        ArrayList<Book> list=new ArrayList<Book>();
        Book book1=new Book(1,"骆驼祥子",55);
        Book book2=new Book(2,"我的爱人",18);
        Book book3=new Book(3,"老人与海",35);
         
        list.add(book1);
        list.add(book2);
        list.add(book3);
        for (int i = 0; i < list.size(); i++) {
            Book b=list.get(i);
            int id=b.getId();
            String name=b.getName();
            double price=b.getPrice();
            out.print("id:"+id+" ,   书名为:"+name+"   ,价格为:"+price);
            %><br><%
        }
         
    %>
 
  </body>
</html>

3.在MySQL中创建Book表,里面id,name,price,

用命令实现,
添加5个图书,
把20元以上的图书价格都修改为18.8,
查看全部图书,
查看价格高于10块钱的全部图书
根据名称删除图书,
把所有名称是“我”开头的图书删除,
删除全部图书。
insert into 表名(列,列,列)values(值,值,值)
delete from 表名 where 删除条件
update 表名 set列名=更新值 where 更新条件
select 列,列,列 …… from 表 where 查询条件

create table book(id int(10) auto_increment primary key,name varchar(50),price double(6,2)); 

用命令实现,添加一个图书,

insert into Book(id,name,price)values(4,"java",88); 

根据名称删除图书,

delete from book where name='java'; 

把所有名称是“我”开头的图书删除,

 delete from book where name like '我%'; 

把20元以上的图书价格都修改为18.8,

update book set price=18.8 where price>20; 

查看全部图书,

select * from book; 

查看价格高于10块钱的全部图书

select * from book where price>10;

删除全部图书,

delete from book;

 

posted on 2022-04-30 23:01  王运聪  阅读(11)  评论(0编辑  收藏  举报