第九周作业

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

 

package homework;

public class Book {
    private String id;
    private String name;
    private double price;
    public String getId() {
        return id;
    }

    public void setId(String 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;
    }

    public Book(String string, String name, double price) {
        super();
        this.id = string;
        this.name = name;
        this.price = price;
    }

    public Book() {
        super();
    }

}




package com.lwk.demo5;

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

public class Test {
    static List<Book> lbs = new ArrayList<Book>();

    static {
        Book b1 = new Book("1001", "西游记", 50.9);
        lbs.add(b1);
        Book b2 = new Book("1002", "红楼梦", 49.9);
        lbs.add(b2);
        Book b3 = new Book("1003", "水浒传", 65.9);
        lbs.add(b3);
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        mnue();
    }

    public static void mnue() {
        for (;;) {
            System.out.println("***********************");
            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、查询所有图书                    *");
            System.out.println("*    5、查询一本图书                    *");
            System.out.println("*    0、退出程序                            *");
            System.out.println("***********************");
            int i = inputInt("请输入要选择的操作:");
            switch (i) {
            case 1:
                addBook();
                break;
            case 2:
                delBook();
                break;
            case 3:
                updateBook();
                break;
            case 4:
                findAllBook();
                break;
            case 5:
                findBookByName();
                break;
            case 0:
                return;
            default:
                System.out.println("输入错误,请重新输入");
                break;
            }
        }
    }

    private static void findBookByName() {
        String name = inputStr("请输入要查找的图书名称");
        int index = 0;
        System.out.println("id\t图书名称\t价格");
        for (Book book : lbs) {
            if (name.equals(book.getName())) {
                System.out.println(book.getId() + "\t" + book.getName() + "\t"
                        + book.getPrice());
            }
            index++;
        }
    }

    private static void findAllBook() {
        System.out.println("id\t图书名称\t价格");
        for (Book book : lbs) {
            System.out.println(book.getId() + "\t" + book.getName() + "\t"
                    + book.getPrice());
        }

    }

    private static void updateBook() {
        String id = inputStr("请输入要修改的图书id");
        int index = 0;
        for (Book book : lbs) {
            if (id.equals(book.getId())) {
                book.setName(inputStr("请输入修改后的名称:"));
                book.setPrice(inputDouble("请输入修改后的价格:"));
                lbs.remove(index);
                lbs.add(index, book);
            }
            index++;
        }
    }

    private static void delBook() {
        String id = inputStr("请输入要删除的图书id");
        int index = 0;
        for (Book book : lbs) {
            if (id.equals(book.getId())) {
                lbs.remove(index);
            }
            index++;
        }

    }

    private static void addBook() {
        String id = inputStr("请输入图书id");
        String name = inputStr("请输入图书名称");
        double price = inputDouble("请输入图书价格");
        Book book = new Book(id, name, price);
        lbs.add(book);
    }

    public static String inputStr(String msg) {
        System.out.print(msg);
        return new Scanner(System.in).nextLine();
    }

    public static int inputInt(String msg) {
        System.out.print(msg);
        return new Scanner(System.in).nextInt();
    }

    public static double inputDouble(String msg) {
        System.out.print(msg);
        return new Scanner(System.in).nextDouble();
    }

}

 

 

 

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="com.yyb.book.Book"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
 <%List<Book> list =new ArrayList<Book>();
   Book book1=new Book(1,"语文",30);
        Book book2=new Book(2,"数学",25);
        Book book3=new Book(3,"英语",31);
        list.add(book1);
        list.add(book2);
        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,
添加一个图书,
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,
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

 

 

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);


delete from book where name='java';

delete from book where name like '我%';

update book set price=18.8 where price>20;

select * from book;

select * from book where price>10;

delete from book;

 

 

posted @ 2022-05-01 09:14  高杨翔  阅读(10)  评论(0编辑  收藏  举报