Spring Boot集成MyBatis方法一：xml配置并自动生成dao层

一、新建Spring Boot工程

（略，参考相关文章）

源码路径：https://gitee.com/sujianfeng/labcloud/tree/master/lab-mybatis

二、build.gradle加入依赖

主要是红色字体的部分

ependencies {    
    implementation('org.springframework.boot:spring-boot-starter-data-jpa')
    implementation('org.springframework.boot:spring-boot-starter-web')
    implementation('de.codecentric:spring-boot-admin-starter-client')
    implementation('org.mybatis.spring.boot:mybatis-spring-boot-starter:1.3.2')
    implementation('org.springframework.cloud:spring-cloud-starter-netflix-eureka-client')
    implementation('com.alibaba:druid:1.1.0')
    runtimeOnly('mysql:mysql-connector-java')
    testImplementation('org.springframework.boot:spring-boot-starter-test')
}

 三、Spring Boot的启动类的注解

@SpringBootApplication
@MapperScan("com.labcloud.labmybatis.module.demo.dao") //用于自动生成dao层实现类（不用手动编写）
@EnableTransactionManagement //启动事务管理
@ComponentScan(basePackages = {"com.labcloud.labmybatis"}) //纳入事务管理包根路径
public class LabMybatisApplication {
    public static void main(String[] args) {
        SpringApplication.run(LabMybatisApplication.class, args);
    }
}

四、application.yml配置

server:
  port: 8203

spring:
  application:
    name: lab-mybatis
  datasource:
    url: jdbc:mysql://localhost:3306/lab
    username: root
    password: 960720
    driver-class-name: com.mysql.cj.jdbc.Driver

mybatis:
  mapperLocations: classpath:mapper/*.xml
  type-Aliases-Package: com.labcloud.labmybatis.module.demo.entity

五、实现代码

（1）代码目录结构

（2）Controller层代码

@RestController
@EnableAutoConfiguration
@RequestMapping("/my-batis")
public class LabUserController {

    @Resource
    private LabUserService labUserService;

    @RequestMapping(value = "/showUser", produces = "application/json;charset=UTF-8")
    @ResponseBody
    public LabUser showUser(HttpServletRequest request, Model model){
        int userId = ConvertUtils.cInt(request.getParameter("id"));
        LabUser user = this.labUserService.getUserById(userId);
        return user;
    }

}

（3）dao层接口定义

public interface LabUserDao {
    int deleteByPrimaryKey(Integer id);

    int insert(LabUser record);

    int insertSelective(LabUser record);

    LabUser selectByPrimaryKey(Integer id);

    int updateByPrimaryKeySelective(LabUser record);

    int updateByPrimaryKey(LabUser record);
}

（4）实体定义

public class LabUser {
    private Integer id;

    private String userName;

    private String password;

    private Integer age;

    public Integer getId() {
        return id;
    }

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

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

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

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}

（5）service接口定义

public interface ILabUserService {
    public LabUser getUserById(int userId);

    boolean addUser(LabUser record);
}

（6）service实现类

@Service
public class LabUserService implements ILabUserService {
    @Resource
    private LabUserDao labUserDao;

    @Override
    public LabUser getUserById(int labUserId) {
        return labUserDao.selectByPrimaryKey(labUserId);
    }

    @Override
    @Transactional
    public boolean addUser(LabUser labUser) {
        boolean result = false;
        try {
            labUserDao.insertSelective(labUser);
            result = true;
        } catch (Exception e) {
            e.printStackTrace();
        }

        return result;
    }
}

（7）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" >
<mapper namespace="com.labcloud.labmybatis.module.demo.dao.LabUserDao" >
    <resultMap id="BaseResultMap" type="com.labcloud.labmybatis.module.demo.entity.LabUser" >
        <id column="id" property="id" jdbcType="INTEGER" />
        <result column="username" property="userName" jdbcType="VARCHAR" />
        <result column="password" property="password" jdbcType="VARCHAR" />
        <result column="age" property="age" jdbcType="INTEGER" />
    </resultMap>
    <sql id="Base_Column_List" >
        id, username, password, age
    </sql>
    <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
        select
        <include refid="Base_Column_List" />
        from lab_user
        where id = #{id,jdbcType=INTEGER}
    </select>
    <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >
        delete from lab_user
        where id = #{id,jdbcType=INTEGER}
    </delete>
    <insert id="insert" parameterType="com.labcloud.labmybatis.module.demo.entity.LabUser" >
        insert into lab_user (id, username, password,
        age)
        values (#{id,jdbcType=INTEGER}, #{userName,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR},
        #{age,jdbcType=INTEGER})
    </insert>
    <insert id="insertSelective" parameterType="com.labcloud.labmybatis.module.demo.entity.LabUser"
            keyProperty="id" useGeneratedKeys="true"
        >
        insert into lab_user
        <trim prefix="(" suffix=")" suffixOverrides="," >
            <if test="id != null" >
                id,
            </if>
            <if test="userName != null" >
                username,
            </if>
            <if test="password != null" >
                password,
            </if>
            <if test="age != null" >
                age,
            </if>
        </trim>
        <trim prefix="values (" suffix=")" suffixOverrides="," >
            <if test="id != null" >
                #{id,jdbcType=INTEGER},
            </if>
            <if test="userName != null" >
                #{userName,jdbcType=VARCHAR},
            </if>
            <if test="password != null" >
                #{password,jdbcType=VARCHAR},
            </if>
            <if test="age != null" >
                #{age,jdbcType=INTEGER},
            </if>
        </trim>
    </insert>
    <update id="updateByPrimaryKeySelective" parameterType="com.labcloud.labmybatis.module.demo.entity.LabUser" >
        update lab_user
        <set >
            <if test="userName != null" >
                username = #{userName,jdbcType=VARCHAR},
            </if>
            <if test="password != null" >
                password = #{password,jdbcType=VARCHAR},
            </if>
            <if test="age != null" >
                age = #{age,jdbcType=INTEGER},
            </if>
        </set>
        where id = #{id,jdbcType=INTEGER}
    </update>
    <update id="updateByPrimaryKey" parameterType="com.labcloud.labmybatis.module.demo.entity.LabUser" >
        update lab_user
        set username = #{userName,jdbcType=VARCHAR},
        password = #{password,jdbcType=VARCHAR},
        age = #{age,jdbcType=INTEGER}
        where id = #{id,jdbcType=INTEGER}
    </update>
</mapper>

（8）单元测试

@RunWith(SpringRunner.class)
@SpringBootTest
@Transactional
public class DemoTest {

    @Autowired
    private LabUserService labUserService;

    @Test
    @Rollback(true)
    public void test(){
        LabUser labUser = new LabUser();
        labUser.setUserName("test1");
        boolean ok = labUserService.addUser(labUser);
        Assert.isTrue(ok, "新增用户失败！");
        LabUser labUser1 = labUserService.getUserById(labUser.getId());
        Assert.isTrue(labUser1 != null, "查询用户失败！");
    }
}

六、运行演示

（1）单元测试

在单元测试带密码DemoTest中，右键执行【Debug ‘’DemoTest】即可

（2）手动测试

结束！