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JSP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

package po;

public class Book {
	private int bid;
	private String bname;
	private double bprice;

	public Book() {
		super();
		// TODO Auto-generated constructor stub
	}

	public Book(int bid, String bname, double bprice) {
		super();
		this.bid = bid;
		this.bname = bname;
		this.bprice = bprice;
	}

	public int getBid() {
		return bid;
	}

	public void setBid(int bid) {
		this.bid = bid;
	}

	public String getBname() {
		return bname;
	}

	public void setBname(String bname) {
		this.bname = bname;
	}

	public double getBprice() {
		return bprice;
	}

	public void setBprice(double bprice) {
		this.bprice = bprice;
	}

	@Override
	public String toString() {
		return "Book [bid=" + bid + ", bname=" + bname + ", bprice=" + bprice + "]";
	}

}

package po;

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

public class Lib {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		List<Book> blist = new ArrayList<>();
		Book b1 = new Book();
		b1.setBid(1);
		b1.setBname("三国");
		b1.setBprice(55);
		blist.add(b1);
		Book b2 = new Book();
		b2.setBid(2);
		b2.setBname("水浒");
		b2.setBprice(45);
		blist.add(b2);
		Book b3 = new Book();
		b3.setBid(3);
		b3.setBname("西游");
		b3.setBprice(35);
		blist.add(b3);
		w: while (true) {
			System.out.println("1.增加2.删除3.修改4.查询");
			System.out.println("输入您的选择：");
			int x = sc.nextInt();
			int i;
			String n;
			double p;
			switch (x) {
			case 1:
				System.out.println("输入Book的id：");
				i = sc.nextInt();
				System.out.println("输入Book的name：");
				n = sc.next();
				System.out.println("输入Book的price：");
				p = sc.nextDouble();
				add(i, n, p, blist);
				break;
			case 2:
				System.out.println("输入Book的id：");
				i = sc.nextInt();
				delete(i, blist);
				break;
			case 3:
				System.out.println("输入Book的id：");
				i = sc.nextInt();
				System.out.println("输入Book的price：");
				p = sc.nextDouble();
				update(i, p, blist);
				break;
			case 4:
				System.out.println("是否查询所有：(y/n)");
				String pd = sc.next();
				if (pd.equals("y")) {
					for (Book book : blist) {
						System.out.println(book.toString());
					}
				} else {
					System.out.println("输入Book的name：");
					n = sc.next();
					List<Book> blist1 = select(n, blist);
					for (Book book : blist1) {
						System.out.println(book.toString());
					}
				}

				break;
			default:

				break w;
			}
		}
	}

	public static void add(int i, String n, double p, List<Book> blist) {
		Book b1 = new Book();
		b1.setBid(i);
		b1.setBname(n);
		b1.setBprice(p);
		blist.add(b1);
	}

	public static void delete(int i, List<Book> blist) {
		for (Book b : blist) {
			if (b.getBid() == i) {
				blist.remove(b);
			}
		}
	}

	public static void update(int i, double p, List<Book> blist) {
		for (Book b : blist) {
			if (b.getBid() == i) {
				b.setBprice(p);
			}
		}
	}

	public static List<Book> select(String n, List<Book> blist) {
		List<Book> blist1 = new ArrayList<>();
		for (Book b : blist) {
			if (b.getBname().equals(n)) {
				blist1.add(b);
			}
		}
		return blist1;
	}
}

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。

<%-- Librsry.jsp --%>
<%@ page language="java" contentType="text/html; charset=utf-8"
	pageEncoding="utf-8"%>
<%@ page import="po.Book"%>
<%@ page import="java.util.List"%>
<%@ page import="java.util.ArrayList"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
</head>
<body>
	<%
		List<Book> blist = new ArrayList<>();
		Book b1 = new Book();
		b1.setBid(1);
		b1.setBname("三国");
		b1.setBprice(55);
		blist.add(b1);
		Book b2 = new Book();
		b2.setBid(2);
		b2.setBname("水浒");
		b2.setBprice(45);
		blist.add(b2);
		Book b3 = new Book();
		b3.setBid(3);
		b3.setBname("西游");
		b3.setBprice(35);
		blist.add(b3);
		for (Book b : blist) {
			int bid = b.getBid();
			String bname = b.getBname();
			double bprice = b.getBprice();

			out.print("<li>商品id&nbsp" + bid + "&nbsp商品名：" + bname + "&nbsp价格：" + bprice + "&nbsp</li>");

		}
	%>
</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

-- 在MySQL中创建Book表，里面id,name,price,用命令实现，
CREATE TABLE Book (
	bid INT auto_increment PRIMARY KEY,
	bname VARCHAR (10),
	bprice DECIMAL (3, 1)
);

-- 添加5个图书
INSERT INTO Book ()
VALUES
	(2, '三国', 19);

INSERT INTO Book (bname, bprice)
VALUES
	('水浒', 45);

INSERT INTO Book (bname, bprice)
VALUES
	('西游', 55);

INSERT INTO Book (bname, bprice)
VALUES
	('红楼梦', 55);

INSERT INTO Book (bname, bprice)
VALUES
	('雪山飞狐', 65);

-- 把20元以上的图书价格都修改为18.8，
UPDATE Book
SET bprice = 18.8
WHERE
	bprice > 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
	bprice > 10;

-- 根据名称删除图书，
DELETE
FROM
	Book
WHERE
	bname = '雪山飞狐';

-- 把所有名称是“我”开头的图书删除，
INSERT INTO Book (bname, bprice)
VALUES
	('我是猫', 75);

DELETE
FROM
	Book
WHERE
	bname LIKE '我%';

-- 删除全部图书。
DELETE
FROM
	Book;
posted @ 2022-04-27 12:38  Y6  阅读(57)  评论(0)    收藏  举报