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
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。
public class Book { int id; String name; int 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 int getPrice() { return price; } public void setPrice(int price) { this.price = price; } public Book(int id, String name, int price) { super(); this.id = id; this.name = name; this.price = price; } @Override public String toString() { return "Book [书籍id:" + id + ", 书籍名称:" + name + ", 书籍价格:" + price + "]"; } }
import java.util.ArrayList; import java.util.List; import java.util.Scanner; public class test { static List<Book>list=new ArrayList<Book>(); static Scanner a=new Scanner(System.in); static{ Book book1=new Book(01, "mysql基础", 50); Book book2=new Book(02, "Spring", 49); Book book3=new Book(03, "Mybatis", 60); list.add(book1); list.add(book2); list.add(book3); } public static void main(String[] args){ menu(); } public static void menu(){ for(;;){ System.out.println("菜单"); System.out.println("1.增加"); System.out.println("2.删除"); System.out.println("3.修改"); System.out.println("4.查询"); System.out.println("请输入要选择的编号:"); int btn=a.nextInt(); switch(btn){ case 1: add(); break; case 2: drop(); break; case 3: update(); break; case 4: search(); break; default:System.out.println("输入错误!"); } } } private static void add(){ System.out.println("请输入要增加的内容:"); System.out.println("图书id:"); int id=a.nextInt(); System.out.println("图书名称:"); String name=a.next(); System.out.println("图书价格:"); int price=a.nextInt(); list.add(new Book(id, name, price)); System.out.println("添加成功!"); } private static void drop(){ System.out.println("请输入你要删除的图书id"); 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) { // TODO: handle exception } } private static void update(){ System.out.println("请输入修改的图书id"); int d=new Scanner(System.in).nextInt(); for (Book book : list) { if (d==book.getId()) { System.out.println("请输入新的图书名称:"); String b1=new Scanner(System.in).next(); System.out.println("请输入新的价格:"); int c1=new Scanner(System.in).nextInt(); book.setName(b1); book.setPrice(c1); System.out.println("修改成功"); } } } private static void search(){ for(int i=0;i<list.size();i++){ System.out.println(list.get(i)); } } }
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
3.在MySQL中创建Book表,里面id,name,price,
create table book( id int(10) auto_increment primary key, name varchar(30), price double(5,2));
用命令实现,
添加一个图书,
insert into Book(id,name,price)values(1,"java",88);
根据名称删除图书,
delete from book where name='红楼梦';
把所有名称是“我”开头的图书删除,
delete from book where name like '我%';
删除全部图书,
delete from book;
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;
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 price>10;