JSP第九次作业
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 zqj;
/*
* 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
*/
public class Book {
private Integer id;
private String name;
private Integer price;
public Book(Integer id, String name, Integer price) {
super();
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 Integer getPrice() {
return price;
}
public void setPrice(Integer price) {
this.price = price;
}
public Book(){
super();
}
public String toString() {
return "book [id=" + id + ", name=" + name + ", price=" + price + "]";
}
}
package zqj; import java.util.List; import java.util.ArrayList; import java.util.Scanner; public class test { static java.util.List<Book> list=new ArrayList<Book>(); static{ Book book1=new Book(1,"mysql",30); Book book2=new Book(2,"java",25); Book book3=new Book(3,"操作系统",31); list.add(book1); list.add(book2); list.add(book3); } public static void main(String[] args) { while(true){ 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("5.退出"); System.out.println("请选择"); Scanner scanner=new Scanner(System.in); int a=scanner.nextInt(); switch (a) { case 1: add(); break; case 2: del(); break; case 3: change(); break; case 4: search(); break; case 5: System.out.println("退出成功"); return; } } } private static void search(){ for(Book book4:list){ System.out.println(book4); } } private static void change(){ System.out.println("请输入需要修改的图书编号"); int update=new Scanner(System.in).nextInt(); for(Book book:list){ if(update==book.getId()){ System.err.println("请输入书名"); String name1=new Scanner(System.in).next(); System.err.println("请输入价格"); int price1=new Scanner(System.in).nextInt(); book.setName(name1); book.setPrice(price1); System.out.println("修改成功"); } } } private static void del(){ System.out.println("请输入删除的图书编号"); int id=new Scanner(System.in).nextInt(); try{ for(Book book:list){ if(list.size()!=0){ if(id==book.getId()){ list.remove(book); System.out.println("删除成功"); } } } }catch(Exception e){ } } private static void add(){ Scanner scanner=new Scanner(System.in); System.err.println("请输入编号"); int idd=scanner.nextInt(); System.err.println("请输入书名"); String name2=scanner.next(); System.err.println("请输入价格"); int price2=scanner.nextInt(); Book book=new Book(idd,name2,price2); list.add(book); System.out.println("添加成功"); } }
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="zqj.Book" %> <%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <html> <% List<Book> list =new ArrayList<Book>(); Book book1 =new Book(1,"马克思主义",66.0); list.add(book1); Book book2 =new Book(2,"自制力",58.0); list.add(book2); Book book3 =new Book(3,"鲁滨逊漂流记",42.0); 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(11) NOT NULL,
`name` varchar(255),
`price` double(10),
)
添加
insert into book values(1,'嘻嘻哈哈',50) update book set price = 18.8 where price > 20
查找
delete from book where name='web';
删除
delete from book where name = '我'