页面登录

package com.itheima.mapper;

import com.itheima.pojo.User;
import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;

public interface Usermapper {
@Select("select * from t_user where uname=#{uname} and pwd=#{pwd}")
User select(@Param("uname")String uname, @Param("pwd")String pwd);
}
package com.itheima.pojo;

public class User {
private String uname;
private String pwd;

public String getUname() {
    return uname;
}

public void setUname(String uname) {
    this.uname = uname;
}

public String getPwd() {
    return pwd;
}

public void setPwd(String pwd) {
    this.pwd = pwd;
}

@Override
public String toString() {
    return "User{" +
            "uname='" + uname + '\'' +
            ", pwd='" + pwd + '\'' +
            '}';
}

}
package com.itheima.web;

import com.itheima.mapper.Usermapper;
import com.itheima.pojo.User;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.example.webdemo.HelloServlet;

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.io.InputStream;
import java.io.PrintWriter;

@WebServlet("/loginservlet")
public class loginservlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String uname= req.getParameter("uname");
String pwd= req.getParameter("pwd");
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
//获取SqlSession对象
SqlSession sqlSession= sqlSessionFactory.openSession();
Usermapper usermapper=sqlSession.getMapper(Usermapper.class);
User user=usermapper.select(uname,pwd);
sqlSession.close();
//变成中文
resp.setContentType("text/html;charset=utf-8");
PrintWriter writer=resp.getWriter();
if(user!=null){
writer.write("登录成功");
}else{
writer.write("登录失败");
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doGet(req,resp);
}
}

<!-- 配置映射文件或映射类 需要修改-->
<!--    Usermapper路径-->
<mappers>
    <!--        <mapper resource="com/itheima/mapper/UserMapper.xml"/>-->
    <package name="com.itheima.mapper"/>
</mappers>

<%@ page contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>

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