package com.itheima.mapper;
import com.itheima.pojo.Brand;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.ResultMap;
import org.apache.ibatis.annotations.Select;
import java.util.List;
public interface BrandMapper {
/*
* 查询所有
* */
@Select("select * from tb_brand")
@ResultMap("brandResultMap")
List<Brand> selectAll();
/*
* 添加
* */
@Insert("insert into tb_brand values (null,#{brandName},#{companyName},#{ordered},#{description},#{status})")
void add(Brand brand);
/*
* 根据Id查询
* */
@Select("select * from tb_brand where id=#{id}")
@ResultMap("brandResultMap")
Brand selectById(int id);
}
package com.itheima.service;
import com.itheima.mapper.BrandMapper;
import com.itheima.pojo.Brand;
import com.itheima.util.SqlSessionFactoryUtils;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import java.util.List;
public class BrandService {
//1. 使用工具类获util取到getSqlSessionFactory
SqlSessionFactory factory = SqlSessionFactoryUtils.getSqlSessionFactory();
/*
* 查询所有
* */
public List<Brand> selectAll(){
// 调用BrandMapper.selectAll()
//2. 获取SqlSession
SqlSession sqlSession = factory.openSession();
//3. 获取BrandMapper
BrandMapper mapper = sqlSession.getMapper(BrandMapper.class);
//4. 调用方法selectAll()
List<Brand> brands=mapper.selectAll();
//返回brand集合，释放资源
sqlSession.close();
return brands;
}
/*
* 添加
* */
public void add(Brand brand){
//2. 获取SqlSession
SqlSession sqlSession = factory.openSession();
//3. 获取BrandMapper
BrandMapper mapper = sqlSession.getMapper(BrandMapper.class);
//调用方法
mapper.add(brand);
//提交事务
sqlSession.commit();
//释放资源
sqlSession.close();
}
/*
* 根据Id查询
* */
public Brand selectById(int id){
//2. 获取SqlSession
SqlSession sqlSession = factory.openSession();
//3. 获取BrandMapper
BrandMapper mapper = sqlSession.getMapper(BrandMapper.class);
//4. 调用方法selectById()
Brand brand = mapper.selectById(id);
//返回brand，释放资源
sqlSession.close();
return brand;
}
}
package com.itheima.web;
import com.itheima.pojo.Brand;
import com.itheima.service.BrandService;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;
@WebServlet("/selectByIdServlet")
public class SelectByIdServlet extends HttpServlet {
private BrandService service=new BrandService();
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.接受id
String id = request.getParameter("id");
//2.调用service查询
Brand brand = service.selectById(Integer.parseInt(id));
//3.储存到request中
request.setAttribute("brand",brand);
//4.转发到update.jsp
request.getRequestDispatcher("/update.jsp").forward(request,response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request,response);
}
}
<%--
Created by IntelliJ IDEA.
User: admin
Date: 2023/6/30
Time: 13:25
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>修改品牌</title>
</head>
<body>
<h3>修改品牌</h3>
<form action="/brand-demo/addServlet" method="post">
品牌名称：<input name="brandName" value="${brand.brandName}"><br>
企业名称：<input name="companyName" value="${brand.companyName}"><br>
排序：<input name="ordered" value="${brand.ordered}"><br>
描述信息：<textarea rows="5" cols="20" name="description">${brand.description}</textarea><br>
状态：
<c:if test="${brand.status == 0}">
<input type="radio" name="status" value="0" checked>禁用
<input type="radio" name="status" value="1">启用<br>
</c:if>
<c:if test="${brand.status == 1}">
<input type="radio" name="status" value="0">禁用
<input type="radio" name="status" value="1" checked>启用<br>
</c:if>
<input type="submit" value="提交">
</form>
</body>
</html>
标签：BrandMapper,回显,修改,brand,案例,sqlSession,import,Brand,itheima From： https://www.cnblogs.com/Karl-hut/p/17516753.html