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

图书类BooK

package tushu;

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

package tushu;

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

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

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

}

public static void creatBookList() {
// TODO Auto-generated method stub
Book b1 = new Book("001", "JSP使用教程", 79.0);
listbooks.add(b1);
Book b2 = new Book("002", "JavaScript", 59.8);
listbooks.add(b2);
Book b3 = new Book("003", "MySQL应用教程", 49.8);
listbooks.add(b3);
}

public static void menu() {
for (;;) {
System.out.println("************************");
System.out.println("* 1.添加图书 *");
System.out.println("* 2.修改图书 *");
System.out.println("* 3.删除图书 *");
System.out.println("* 4.查询图书 *");
System.out.println("* 5.退出程序 *");
System.out.println("************************");
int i = inputInt("请选择你的操作:");
switch (i) {
case 1:
addBook();
break;
case 2:
updateBook();
break;
case 3:
delBook();
break;
case 4:
findBook();
break;
case 5:
return;
default:
System.out.println("输入错误,请重新输入");
break;
}
}
}

private static void findBook() {
// TODO Auto-generated method stub
System.out.println("id 图书名称图书价格");
for (Book book : listbooks) {
System.out.println(book.getId() + " " + book.getName() + " "
+ book.getPrice());
}

}

private static void delBook() {
// TODO Auto-generated method stub
String id = inputStr("请输入要删除图书的id");
for (int i = 0; i < listbooks.size(); i++) {
Book book = listbooks.get(i);
if (id.equals(book.getId())) {
listbooks.remove(i);
}
}

}

private static void updateBook() {
// TODO Auto-generated method stub
String id = inputStr("请输入要修改的图书id");
for (int i = 0; i < listbooks.size(); i++) {
Book book = listbooks.get(i);
if (id.equals(book.getId())) {
book.setName(inputStr("请输入修改后的图书名称："));
book.setPrice(inputDouble("请输入修改后的图书价格"));
listbooks.remove(i);
listbooks.add(i, book);
}
}

}

private static void addBook() {
// TODO Auto-generated method stub
String id = inputStr("请输入要添加的图书id");
String name = inputStr("请输入要添加的图书名称");
double price = inputDouble("请输入要添加的图书价格");
Book book = new Book(id, name, price);
listbooks.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 language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ page import="tushu.Book"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
</head>

<body>
    <%
        List<Book> listbooks = new ArrayList<Book>();
        Book b1 = new Book("1", "JSP使用教程", 49.8);
        listbooks.add(b1);
        Book b2 = new Book("2", "JavaScript", 59.8);
        listbooks.add(b2);
        Book b3 = new Book("3", "MySQL应用教程", 49.8);
        listbooks.add(b3);
        for (int i = 0; listbooks != null && i < listbooks.size(); i++) {
            out.print(listbooks.get(i).getId() + ": " + listbooks.get(i).getName() + "  "
                    + listbooks.get(i).getPrice() + "<br>");
        }
    %>
</body>
</html>

3.在MySQL中创建Book表，里面id,name,price,
用命令实现，

create database books;

use books;

create table book(
id int(10),
name varchar(10),
price float
);
insert into book values('1','我我我我我我我','01.11');
insert into book values('2','book2','22.22');
把20以上的价格修改成18.8
update book set price=18.8 where price>20;
查找所以书
select * from book;
查看价格高于10块的全部图书
 select * from book where price>10;
把所有名称是“我”开头的图书删除
 delete from book where name like '我%';
删除全部图书
 delete from book;

posted @ 2022-04-29 21:58 叶鑫宇阅读(33) 评论(0) 收藏举报

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第九周作业

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