案例--用户登录

所有坐标

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.tomcat.maven</groupId>
            <artifactId>tomcat7-maven-plugin</artifactId>
            <version>2.2</version>
        </plugin>
    </plugins>
</build>


    <dependencies>
<!--        mysql-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.34</version>
        </dependency>

<!--导入servlet插件-->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>


        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.6</version>
        </dependency>
<!--mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>

    </dependencies>

mybatis-config.xml文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <!--<properties resource="dbconfig.properties"/>-->
    <!--创建别名-->
    <typeAliases>
        <package name="com.avb.pojo"/>
    </typeAliases>

    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>

<property name="url" value="jdbc:mysql:///db1?useSSL=false&amp;useServerPrepStmts=true"/>

//这里修改成自己需要用的数据库 <property name="username" value="root"/> <property name="password" value="root"/> </dataSource> </environment> </environments> <mappers> <!--<mapper resource="com/avb/Mapper/UserMapper.xml"/>--> <!--mapper代理方式--> <package name="com.avb.Mapper"/> </mappers> </configuration>

在Mapper文件夹下创建接口文件在resource文件夹下创建映射文件（两者必须相同路径）

映射文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!--namespace：名称空间。写接口给的全类名，相当于告诉MyBatis这个配置文件是实现哪个接口的。-->

<mapper namespace="com.avb.Mapper.UserMapper">
    <!--resultType=""指定查询数据封装结果的时候使用自定义封装规则-->
    <!--&lt;!&ndash;type指定为哪个javaBean自定义封装规则，id是唯一标识&ndash;&gt;
    <resultMap id="mycat" type="smq.javabean.Cat">
        &lt;!&ndash;id指定主键列的对应规则，column指定哪一列是主键列，property指定cat的哪个属性封装id这个列数据&ndash;&gt;
        <id column="id" property="id"/>
        &lt;!&ndash;普通列&ndash;&gt;
        <result column="cName" property="name"/>
        <result column="cgender" property="gender"/>
        <result column="cAge" property="age"/>
    </resultMap>-->

</mapper>

在接口文件中创建sql语句，由于这个sql语句比较简单可以直接用注解的方式创建。

package com.avb.Mapper;

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

public interface UserMapper {

    @Select("select * from user where username = #{username} and password = #{password}")
    User select(@Param("username") String username, @Param("password") String password);
}

登录界面html文件

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="loginDiv">

<form action="loginServlet" method="post" id="form">

<p>username:<input id="username" name="username" type="text"></p> 

<p>password:<input id="password" name="password" type="password"></p> 

<div id="subDiv">

 <input type="submit" class="button" value="login up"> 

<input type="reset" class="button" value="reset"> <a href="regiseter.html">没有账号？点击注册</a> 
</div>
 </form>
 </div> 
</body> 
</html>

servlet文件

package com.avb.web;

import com.avb.Mapper.UserMapper;
import com.avb.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 java.io.*;
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;

@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
    private String message;

    public void init() {

    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
    //1、接收用户名和密码
        String username = request.getParameter("username");
        String password = request.getParameter("password");
    //2、调用MyBatis完成查询
    //2.1获取SqlSessionFactory对象
    String resource = "mybatis-config.xml";
    InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
    //2.2获取SqlSession对象

        SqlSession sqlSession = sqlSessionFactory.openSession();
    //2.3获取Mapper

        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
    //2.4调用方法

        User user = userMapper.select(username,password);
    //2.5释放资源
        sqlSession.close();
        //获取字符输出流，并设置content type
        response.setContentType("text/html;charset=utf-8");
        PrintWriter writer = response.getWriter();
        //3.判断user释放为null
        if(user != null){
            writer.write("登录成功");
        }
        else{
            writer.write("登录失败");
        }




    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException {
        this.doGet(request, response);
    }
}

posted on 2023-11-18 21:19 na2co3- 阅读(9) 评论(0) 编辑收藏举报

刷新页面返回顶部

公告