第九周上机作业
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 test; public class Book { private Integer id; private String name; private double price; // 无参函数构造 public Book(){ super(); } // 有参函数构造 public Book(int id,String name,double price){ 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 double getPrice() { return price; } public void setPrice(double price) { this.price = price; } }
package test; import java.util.List; import java.util.ArrayList; import java.util.Scanner; public class testClass { /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub List<Book> list = new ArrayList<Book>(); Book b = new Book(); Book b1 = new Book(); b1.setId(1); b1.setName("西游记"); b1.setPrice(54.6); Book b2 = new Book(); b2.setId(2); b2.setName("红楼梦"); b2.setPrice(45.2); Book b3 = new Book(); b3.setId(3); b3.setName("水浒传"); b3.setPrice(35.7); list.add(b1); list.add(b2); list.add(b3); show(list, b); System.out.println("-------------"); } public static void show(List<Book> list,Book b){ System.out.println("开始你的操作"); 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("-------------"); select(list,b); } public static void select(List<Book> list,Book b){ Scanner input = new Scanner(System.in); int k = input.nextInt(); switch (k) { case 1: System.out.println("添加图书的的id："); b.setId(new Scanner(System.in).nextInt()); System.out.println("添加图书名称："); b.setName(new Scanner(System.in).next()); System.out.println("添加图书的价格："); b.setPrice(new Scanner(System.in).nextDouble()); list.add(b); System.out.println("添加成功"); show (list,b); System.out.println("-------------"); break; case 2: System.out.println("输入你要删除图书的id"); int id = input.nextInt(); for (int i = 0 ;i<list.size() ;i++) { if (list.get(i).getId().equals(id)) { list.remove(i); } } System.out.println("已经删除！"); show(list,b); break; case 3: System.out.println("请输入你要修改图书的id"); int changeId = input.nextInt(); for (int i = 0; i < list.size(); i++) { if (list.get(i).getId().equals(changeId)) { list.remove(i); System.out.println("输入修改之后的图书名称："); String name = input.next(); System.out.println("输入修改之后的图书价格："); Double price = input.nextDouble(); Book b0 = new Book(changeId,name,price); list.add(b0); break; } } System.out.println("修改成功"); show(list,b); case 4: for (int i = 0; i< list.size(); i++) { System.out.println(list.get(i).getId() + "." + list.get(i).getName() + "," + list.get(i).getPrice()); } show(list, b); break; } } }
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="test.Book"%> <html> <head> <title>My JSP 'index.jsp' starting page</title> </head> <body> <div style="background-color:skyblue;width=300px;height=100px"> <% List<Book> list = new ArrayList<Book>(); Book b1 = new Book(1, "水浒传", 54.5); Book b2 = new Book(2, "西游记", 45.6); Book b3 = new Book(3, "红楼梦", 55.82); list.add(b1); list.add(b2); list.add(b3); for (int i = 0; i < list.size(); i++) { out.print(list.get(i).getId() + "." + list.get(i).getName() + "," + list.get(i).getPrice()+"<br>"); } %> </div> </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
# 建表 create table book( id double(100,10) primary key auto_increment, name varchar(10) not null , price double(100,10) ); #插入数据 insert into book (name,price) values('西游记',24.5),('我和我',14.5),('重生之天才小子',10); insert into book (name,price) values('三国演义',25),('水浒传',16),('红楼梦',19.6); #查询价格大于10的书籍信息 select * from book where price>10; #查询所有书籍信息 select * from book; #将价格大于20的书籍的价格改为18.8 update book set price=18.8 where price>20; #删除”我“开头的书籍信息 delete from book where name like'我%'; #删除指定名称的书籍信息 delete from book where name='重生之天才小子'; #删除所有书籍信息 delete from book; #删除表 drop table book;
