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 zuoye;

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

package zuoye;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class book1 {

    static List<book> listbooks = new ArrayList<book>();
    public static void main(String[] args) {
                creatBookList();
                menu();

            }

            public static void creatBookList() {
                book b1 = new book(1, "书1",11);
                listbooks.add(b1);
                book b2 = new book(2, "书2",22);
                listbooks.add(b2);
                book b3 = new book(3, "书3",33);
                listbooks.add(b3);
            }

            public static void menu() {
                for (;;) {
                    System.out.println("1.添加,2.修改,3.删除,4.查询,5.退出");
                    int a = inputInt("请输入：");
                    switch (a) {
                    case 1:
                        add();
                        break;
                    case 2:
                        update();
                        break;
                    case 3:
                        del();
                        break;
                    case 4:
                        find();
                        break;
                    case 5:
                        return;
                    default:
                        System.out.println("输入错误");
                        break;
                    }
                }
            }

            private static void find() {
                // TODO Auto-generated method stub
                for (book book : listbooks) {
                    System.out.println("id:"+book.getId() + ",书名：" + book.getName() + "，价格："
                            + book.getPrice());
                }

            }

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

            }

            private static void add() {
                book book = new book();
                int id = inputInt("请输入要添加的id");
                String name = inputStr("请输入要添加的名称");
                double price = inputDouble("请输入要添加的价格");
                book.setId(id);
                book.setName(name);
                book.setPrice(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="zuoye.book"%>
<!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, "书1", 10);
        listbooks.add(b1);
        book b2 = new book(2, "书2", 20);
        listbooks.add(b2);
        book b3 = new book(3, "书3", 30);
        listbooks.add(b3);
        for (int i = 0; listbooks != null && i < listbooks.size(); i++) {
            out.print("id: "+listbooks.get(i).getId() +", name: "+ listbooks.get(i).getName() + ", price: "+ 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，
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(10) auto_increment primary key,
    -> name varchar(50),
    -> price double(3,2));
   );
#插入数据
 insert into book (id,name,price) values(1,'书1',10),(2,'书2',20),(3,'书3',30);
#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;