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

   

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package wn;


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


public class test {
static List<book> list = new ArrayList<book>();
static {
book book1 = new book(1, "JavaWeb", 36.00);
book book2 = new book(2, "JSP", 52.00);
book book3 = new book(3, "网络安全", 41.00);
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");
}


}

 
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package wn;


public class book {
private int id;
private String name;
private double price;


@Override
public String toString() {
return "book [id=" + id + ", name=" + name + ", price=" + price + "]";
}


public int getId() {
return id;
}


public void setId(int 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(int i, String name, double price) {
super();
this.id = i;
this.name = name;
this.price = price;
}


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

 
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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"%>

<html>
<head>

<title>My JSP 'd1.jsp' starting page</title>

</head>
<%@ page import="wn.book"%>

<body>
<%
List<book> list =new ArrayList<book>();
book book1=new book(1,"JavaWeb",56.00);
book book2=new book(2,"网络安全",32.00);
book book3=new book(3,"JSP",41.00);
list.add(book1);
list.add(book2);
list.add(book3);
for (book book4 : list){
out.print(book4+"<br>");}
%>
</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

 
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create table books{
    id int not null,
    name varchar()
    price decimal,
    primary key(id)
          };
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添加2个图书
 insert into Book(id,name,price)values(1,"斗罗大陆",50.00)
 insert into Book(id,name,price)values(2,"庆余年",43.00);
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把20元以上的图书价格都修改为18.8,
 update book set price=18.8 where price>20;
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查看全部图书
 select *from book; 
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查看价格高于10块的全部图书
 select * from book where price>10;
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把所有名称是“我”开头的图书删除
 delete from book where name like '我%'; 
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删除全部图书
 delete from book;
posted @ 2022-07-03 22:02  欧阳晨  阅读(4)  评论(0编辑  收藏  举报