mybatis基本项目搭建

第一步.新建数据库，导入依赖

1.新建数据库表,user

2.导入依赖

 <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>

 

第二步.新建pojo实体类，user类

//新建用户实体类user
package pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
    private Integer userId;
    private String userName;
    private String userEmail;
    private Integer countryId;
    private Integer depId;
    private Integer version;
    private Integer deleted;
}

 

第三步:.新建mapper类和xml文件

//用户类接口 userMapper
package mapper;
import pojo.User;
import java.util.List;
import java.util.Map;
public interface UserMapper {
    public List<User> getUserList();
    public List<User> getUserList2();
    public User getUser(Integer id);
    public Integer addUser(User user);
    public Integer addUser2(Map<String,Object> map);
    public void updateUser(User user);
    public void deleteUser(Integer id);

}

//用户接口的xml文件 userMapper.xml

<?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">
<!--绑定一个操作数据库的接口-->
<mapper namespace="mapper.UserMapper">
    <!--查询    -->
    <!--本来这里的resultType要写全限定类名，但是在mybaits-config.xml文件中配置了别名user后，这里可以直接写user-->
    <select id="getUserList" resultType="user">
        select * from user
    </select>

    <!--使用resultmap 解决实体类和数据库字段不一致的问题，这里我故意把实体类的email 改为userEmail   -->
    <resultMap id="userMap" type="user">
        <!-- column是数据库中的字段名，  property是实体类的属性     -->
        <result column="email" property="userEmail"></result>
    </resultMap>
    <select id="getUserList2" resultMap="userMap">
        select * from user
    </select>


    <select id="getUser" parameterType="Integer" resultType="user">
        select * from user where userId=#{id}
    </select>

<!--    parameterTypes 是一个实体类，那么sql 语句里面的参数必须和实体类的属性一致-->
    <insert id="addUser" parameterType="user" >
        insert into user (userId,userName) values(#{userId},#{userName})
    </insert>
<!--    //parameterTypes 是一个hashmap，那么sql 语句里面的参数不用和实体类的属性一致-->
    <insert id="addUser2" parameterType="map" >
        insert into user (userId,userName) values(#{uId},#{uName})
    </insert>

    <update id="updateUser" parameterType="pojo.User">
        update user set userName=#{userName},email=#{email} where userId=#{userId}
    </update>

    <delete id="deleteUser" parameterType="Integer">
        delete from  user where userId=#{userId}
    </delete>
</mapper>

 

第四步:新建连接的工具类

package myUntil;

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.IOException;
import java.io.InputStream;

public class MybatisUntil {
    private static SqlSessionFactory sqlSessionFactory;

    static {

        try {
            //使用mybatis 第一步，获取sqlSessionFactory对象，这个对象时生成sqlSession的
            String resource= "mybatis-config.xml";
            InputStream inputStream= Resources.getResourceAsStream(resource);
            sqlSessionFactory=new SqlSessionFactoryBuilder().build(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    //有了sqlSessionFactory，我们既可以用sqlSessionFactory来open 一个个的sqlSession
    //sqlSession是可以操作数据库，他包含了所有的sql 语句操作
    public static SqlSession getSqlSession(){
        return  sqlSessionFactory.openSession();
    }
}

 

第五步:新建mybatis 的核心配置文件

<?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>
    <!-- 配置日志文件   -->
    <settings>
<!--        <setting name="logImpl" value="STDOUT_LOGGING"/>-->
        <setting name="logImpl" value="log4j"/>
<!--    开启驼峰命名    -->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
<!--    <properties resource="db.properties"/>-->
    <!--别名    -->
    <typeAliases>
<!--        &lt;!&ndash;设置User类的别名为user        &ndash;&gt;-->
<!--        <typeAlias type="pojo.User" alias="user"></typeAlias>-->
<!--        设置pojo包下的所有实体类的别名为类名的首字母小写  -->
        <package name="pojo"/>
    </typeAliases>

    <environments default="develoment">
        <environment id="develoment">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://47.112.227.192:3306/spring?useUnicode=true&amp;characterEncoding=utf-8&amp;useSSL=false&amp;serverTimezone=GMT%2B8"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>

    <!--每一个mapper 都要在mybatis 的核心配置文件中注册    -->
    <mappers >
<!--        用resource映射的话就用全路径-->
        <mapper resource="mapper/studentMapper.xml"></mapper>
<!--        <mapper resource="mapper/studentMapper.xml"></mapper>-->
<!--    用class 映射的话，要用接口的类的全限定类名    -->
<!--        <mapper class="mapper.StudentMapper"></mapper>-->
        <mapper resource="mapper/teacherMapper.xml"></mapper>
    </mappers>
</configuration>

 

第六步:新建log4j.properties文件

### 设置###
log4j.rootLogger = debug,console,file

### 输出信息到控制抬 ###
log4j.appender.console = org.apache.log4j.ConsoleAppender
log4j.appender.console.Target = System.out
log4j.appender.console.Threshold = DEBUG 
log4j.appender.console.layout = org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern = [%-5p] %d{yyyy-MM-dd HH:mm:ss,SSS} method:%l%n%m%n

### 输出DEBUG 级别以上的日志到=E://logs/error.log ###
log4j.appender.file = org.apache.log4j.DailyRollingFileAppender
log4j.appender.file.File = ./logs/log.log
log4j.appender.file.Append = true
log4j.appender.file.MaxFilesSize=10mb
log4j.appender.file.Threshold = DEBUG 
log4j.appender.file.layout = org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern = %-d{yyyy-MM-dd HH:mm:ss}  [ %t:%r ] - [ %p ]  %m%n

### 日志输出级别 ###
log4j.logger.org.mybatis =debug
log4j.logger.java.sql =debug
log4j.logger.java.sql.Statement =debug
log4j.logger.java.sql.ResultSet =debug
log4j.logger.java.sql.Preparedstatement =debug

 

第七步:新建测试

package test;

import com.sun.istack.internal.logging.Logger;
import mapper.UserMapper;
import myUntil.MybatisUntil;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
import pojo.User;

import java.util.HashMap;
import java.util.List;

public class Mytest {
     static Logger logger=Logger.getLogger(UserMapper.class);

    //查询所有用户的方法
    @Test
    public void getUserList(){

        //通过我们自己编写的工具类获取sqlSession对象
        SqlSession sqlSession=MybatisUntil.getSqlSession();
        //通过getMapper获取接口
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);

        List<User> userList = userMapper.getUserList();
        for (User user : userList) {
            System.out.println(user);
        }
        //这里记得关闭，不然会造成资源浪费
        sqlSession.close();
    }
    //查询所有用户的方法,实体类把email改为userEmail,然后在xml 加resultMap
    @Test
    public void getUserList2(){
        //通过logger 输出日志
        logger.info("进入了这个方法");
        //通过我们自己编写的工具类获取sqlSession对象
        SqlSession sqlSession=MybatisUntil.getSqlSession();
        //通过getMapper获取接口
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);

        List<User> userList = userMapper.getUserList2();
        for (User user : userList) {
            System.out.println(user);
        }
        //这里记得关闭，不然会造成资源浪费
        sqlSession.close();
    }



    //查询单个用户的方法
    @Test
    public void getUser(){
        //通过我们自己编写的工具类获取sqlSession对象
        SqlSession sqlSession=MybatisUntil.getSqlSession();
        //通过getMapper获取接口
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);

        User user=userMapper.getUser(1);
        System.out.println("user:"+user);

        sqlSession.close();
    }

    //添加用户的方法(参数用实体类，这样的话，xml里面的字段必须和实体类的字段一致)
    @Test
    public void addUser(){
        //通过我们自己编写的工具类获取sqlSession对象
        SqlSession sqlSession=MybatisUntil.getSqlSession();
        //通过getMapper获取接口
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);

        User user=new User();
        user.setUserId(10);
        user.setUserName("甚平");
        userMapper.addUser(user);
        System.out.println("加入用户成功");
        //提交事务,低版本不会自动提交事务
        sqlSession.commit();
        sqlSession.close();
    }


    //添加用户的方法(参数用map类，这样的话，xml里面的字段不用和实体类的字段一致)
    @Test
    public void addUser2(){
        //通过我们自己编写的工具类获取sqlSession对象
        SqlSession sqlSession=MybatisUntil.getSqlSession();
        //通过getMapper获取接口
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);

        HashMap<String,Object> hashMap=new HashMap<String, Object>();
        hashMap.put("uId",20);
        hashMap.put("uName","四皇凯多");
        userMapper.addUser2(hashMap);

        System.out.println("加入用户成功");
        //提交事务,低版本不会自动提交事务
        sqlSession.commit();
        sqlSession.close();
    }

    //更新用户的方法
    @Test
    public void updateUser(){
        //通过我们自己编写的工具类获取sqlSession对象
        SqlSession sqlSession=MybatisUntil.getSqlSession();
        //通过getMapper获取接口
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);

        User user=new User();
        user.setUserId(10);
        user.setUserName("海侠甚平22222");
        user.setUserEmail("hxsp@qq.com");
        userMapper.updateUser(user);
        System.out.println("更新成功");

    }

    //删除用户的方法
    @Test
    public void deleteUser(){
        //通过我们自己编写的工具类获取sqlSession对象
        SqlSession sqlSession=MybatisUntil.getSqlSession();
        //通过getMapper获取接口
        UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
        userMapper.deleteUser(2);
        System.out.println("删除成功");

        sqlSession.commit();
        sqlSession.close();
    }

}