Mybatis基本使用

1、创建maven项目，导入mybatis依赖。

<dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.4.SNAPSHOOT</version>
        </dependency>

2、创建MybatisConfig.xml配置连接文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org/DTD Config 3.0" "http://mybatis.org/dtd/mybatis-3-config.dtd">
<!-- MyBatis的全局配置文件 -->
<configuration >
    <!-- 1.配置环境，可配置多个环境（比如：develop开发、test测试） -->
    <environments default="develop">
        <environment id="develop">
            <!-- 1.1.配置事务管理方式：JDBC/MANAGED
            JDBC：将事务交给JDBC管理（推荐）
            MANAGED：自己管理事务
              -->
            <transactionManager type="JDBC"></transactionManager>
            <!-- 1.2.配置数据源，即连接池 JNDI/POOLED/UNPOOLED
                JNDI：已过时
                POOLED：使用连接池（推荐）
                UNPOOLED：不使用连接池
             -->
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/user-mode?characterEncoding=utf-8"/>
                <property name="username" value="root"/>
                <property name="password" value="1234qwer"/>
            </dataSource>
        </environment>
    </environments>
    <!-- 2.导入Mapper配置文件，如果mapper文件有多个，可以通过多个mapper标签导入-->
    <mappers>
        <mapper resource="mapper/UserMapper.xml"/>
    </mappers>
</configuration>

3、创建User用户实体类

@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class User {
    private Long id;

    /**
     * 名称
     */
    private String name;

    /**
     * 邮箱
     */
    private String email;

    /**
     * 手机号
     */
    private String phoneNumber;
}

4、创建用户model接口

@Mapper
public interface UserMapper {

    List<User> getPageUser(@Param("name") String name);

    void insertUser(User user);

    void updateUser(User user);

    void deletetUser(Long userId);
}

5、创建映射文件UserMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org/DTD Mapper 3.0" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.itmy.dao.UserMapper">

    <resultMap id="userRmap" type="com.itmy.model.entity.User">
        <result jdbcType="VARCHAR" javaType="java.lang.String" column="name" />
    </resultMap>

    <select id="getPageUser" resultType="com.itmy.model.entity.User" parameterType="string">
        select * from tb_user
        <where>
            <if test="name != null and '' != name">
                name like CONCAT('%',#{name},'%');
            </if>
        </where>
    </select>

    <insert id="insertUser" parameterType="com.itmy.model.entity.User">
        INSERT INTO `tb_user`
        (`name`, `account`,`password`, `email`,phone_number,remark)
        VALUES
        (#{name}, #{account}, #{password}, #{email},#{phoneNumber},#{remark});
    </insert>

    <update id="updateUser" parameterType="com.itmy.model.entity.User">
        UPDATE tb_user
        <set>
            <if test="name != null and '' != name">
                name = #{name},
            </if>
            <if test="account != null and '' != account">
                account = #{account},
            </if>
            <if test="password != null and '' != password">
                password = #{password},
            </if>
            <if test="email != null and '' != email">
                email = #{email},
            </if>
            <if test="phoneNumber != null and '' != phoneNumber">
                phone_number = #{phoneNumber},
            </if>
            <if test="remark != null and '' != remark">
                remark = #{remark},
            </if>
        </set>
        where id = #{id}
    </update>

    <delete id="deletetUser" parameterType="java.lang.Long">
        DELETE FROM tb_user WHERE id = #{userId}
    </delete>
</mapper>

6、在测试类中编写测试文件MTest.java

public class Test {

    InputStream inputStream;

    SqlSession sqlSession;
    @Before
    public void beforeSql() throws IOException {
        inputStream = Resources.getResourceAsStream("MybatisConfig.xml");
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        sqlSession = sqlSessionFactory.openSession();
    }

    @org.junit.Test
    public void querySql(){
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        List<User> pageUser = userMapper.getPageUser(null);
        for (int i = 0; i < pageUser.size(); i++) {
            System.out.println(pageUser.get(i));
        }
    }

    @org.junit.Test
    public void insertSql(){
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user=new User();
        user.setAccount("aaaaa@qq.com");
        user.setEmail("aaaaa@qq.com");
        user.setName("掌声");
        user.setPassword("SDWAR!@");
        user.setPhoneNumber("12345");
        user.setRemark("测试优化信息");
        userMapper.insertUser(user);
        sqlSession.commit();
        System.out.println();
    }

    @org.junit.Test
    public void updateSql(){
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        User user=new User();
        user.setAccount("bbabbb@qq.com");
        user.setEmail("bbbabb@qq.com");
        user.setName("掌声bb");
        user.setPassword("SDbbWAR!@");
        user.setPhoneNumber("12345");
        user.setRemark("测试优化b信息");
        user.setId(5L);
        userMapper.updateUser(user);
        System.out.println();
        sqlSession.commit();
    }

    @org.junit.Test
    public void deleteSql(){
        UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
        userMapper.deletetUser(6L);
        System.out.println();
        sqlSession.commit();
    }


    @After
    public void afterSql() throws IOException {
        sqlSession.close();
        inputStream.close();
    }
}