使用IDEA的Maven工程搭建MyBatis框架

创建Maven工程

创建一个默认的Maven工程，不需要勾选任何一项模板

设置项目名称，以及所属单位，点击finish创建完成

导入所需要的依赖

所需要的依赖有mybatis核心依赖包，MySQL驱动包，以及为了方便测试需要的junit包，在下面弹出的提示框中点击Enable Auto-Import，表示自动导入需要的依赖

在resources目录下创建配置文件

创建mybatis-config.xml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>
    <!-- 环境配置 -->
    <!--这里使用了外部导入配置，需要创建一个mybatis.properties文件-->
    <properties resource="mybatis.properties"></properties>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <!-- 数据库连接相关配置 ,这里动态获取mybatis.properties文件中的内容-->
            <dataSource type="POOLED">
                <property name="driver" value="${driver}" />
                <property name="url" value="${url}" />
                <property name="username" value="${username}" />
                <property name="password" value="${password}" />
            </dataSource>
        </environment>
    </environments>
    <!-- mapping文件路径配置 -->
    <mappers>
        <mapper resource="mapper/UserMapper.xml"/>
    </mappers>

</configuration>

创建mybatis.properties文件

username=root
password=1234
url=jdbc:mysql://localhost:3306/mybatis?characterEncoding=UTF-8&useSSL=false
driver=com.mysql.jdbc.Driver

在MySQL数据库中创建对应的数据表

-- ----------------------------
-- Table structure for commodity
-- ----------------------------
DROP TABLE IF EXISTS `commodity`;
CREATE TABLE `commodity`  (
  `id` int(11) NOT NULL,
  `name` varchar(55) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `madein` varchar(55) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `inprice` int(11) NOT NULL,
  `outprice` int(11) NOT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of commodity
-- ----------------------------
INSERT INTO `commodity` VALUES (1, '鱼豆腐', '中国', 2, 3);
INSERT INTO `commodity` VALUES (2, '辣条', '中国', 5, 10);
INSERT INTO `commodity` VALUES (3, '辣条', '中国', 5, 10);

-- ----------------------------
-- Table structure for user
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user`  (
  `id` int(11) NOT NULL,
  `name` varchar(55) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `password` varchar(55) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES (1, '西瓜', '123');
INSERT INTO `user` VALUES (2, '橘子', '123');

创建对应的实体类

User实体类

package com.youzi;

public class User {
    private Integer id;
    private String name;
    private String password;

    public User() {
    }

    public User(Integer id, String name, String password) {
        this.id = id;
        this.name = name;
        this.password = password;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

编写对应的Mapper文件

<?xml version="1.0" encoding="UTF-8"?>
<!--约束-->
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<!-- mapper为映射的根节点，namespace指定Dao接口的完整类名-->
<!--mybatis会依据这个接口动态创建一个实现类去实现这个接口，而这个实现类是一个Mapper对象-->
<!--namespace值包名的命名空间-->
<mapper namespace="com.youzi.model">
    <resultMap type="com.youzi.model.User" id="userMap">
        <id column="id" property="id"/>
        <result column="name" property="name"/>
        <result column="password" property="password"/>
    </resultMap>
    <!--查询语句-->
    <select id="findUserById" parameterType="int" resultMap="userMap">
         select * from user where id = #{id}
    </select>
    <!--新增语句-->
    <insert id="istUser" parameterType="com.youzi.model.User">
         insert into user values(#{id},#{name},#{password})
    </insert>
    <!--删除语句-->
    <delete id="delUserById" parameterType="int">
        delete from user where id=#{id}
    </delete>
    <!--更新语句-->
    <update id="uptUserById" parameterType="com.youzi.model.User">
        update user set name=#{name},password=#{password} where id=#{id}
    </update>
</mapper>

测试代码

package Test;

import com.youzi.model.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.junit.Test;

import java.io.Reader;

public class UserTest {
    @Test
    public void findUserById(){
        //mybatis-config.xml文件路径
        String resources = "mybatis-config.xml";
        SqlSession sqlSession = null;
        try{
            Reader reader = Resources.getResourceAsReader(resources);
            //获取sqlSession
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
            sqlSession = sqlSessionFactory.openSession();
            //执行sql语句
            User user = sqlSession.selectOne("com.youzi.model.User.findUserById",1);
            System.out.println(user);
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            //关闭sqlSession
            if(sqlSession!=null){
                sqlSession.close();
            }
        }
    }
}