Spring Boot整合MyBatis+MySQL实战指南（Java 1.8 + 单元测试）

一、环境准备

• 开发工具：IntelliJ IDEA 2023.1 + JDK 1.8.0_382+ Maven3.6.3
• 数据库：MySQL 8.0.21
• 依赖版本：

  <parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.7.12</version>
  </parent><dependencies><!-- Web支持 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- MyBatis支持 --><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>2.3.0</version></dependency><!-- MySQL驱动 --><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.21</version></dependency><!-- 测试支持 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency>
  </dependencies>
  

二、项目结构

src/main/java
└─com.shuanglibi.demo├─controller├─service├─mapper├─entity└─DemoApplication.java
src/main/resources├─application.yml└─mapper└─UserMapper.xml
src/test/java└─com.shuanglibi.demo└─service└─UserServiceTest.java

三、核心代码实现

1. 配置文件 application.yml

spring:datasource:url: jdbc:mysql://localhost:3306/testdb?useSSL=false&serverTimezone=UTC&useUnicode=true&characterEncoding=UTF-8username: rootpassword: xxxxxxdriver-class-name: com.mysql.cj.jdbc.Drivermybatis:mapper-locations: classpath:mapper/*.xmltype-aliases-package: com.shuanglibi.demo.entityconfiguration:map-underscore-to-camel-case: true

2. 实体类 User.java

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {private Long id;private String name;private Integer age;private LocalDateTime createTime;
}

3. Mapper接口 UserMapper.java

@Mapper
public interface UserMapper {@Select("SELECT * FROM user WHERE id = #{id}")User findById(Long id);@Insert("INSERT INTO user(name, age, create_time) VALUES(#{name}, #{age}, NOW())")@Options(useGeneratedKeys = true, keyProperty = "id")int insert(User user);@Update("UPDATE user SET name=#{name}, age=#{age} WHERE id=#{id}")int update(User user);@Delete("DELETE FROM user WHERE id=#{id}")int delete(Long id);
}

4. Service层 UserService.java

@Service
@RequiredArgsConstructor
public class UserService {private final UserMapper userMapper;public User getUserById(Long id) {return userMapper.findById(id);}public int createUser(User user) {return userMapper.insert(user);}public int updateUser(User user) {return userMapper.update(user);}public int deleteUser(Long id) {return userMapper.delete(id);}
}

四、单元测试实现（JUnit 5）

1. 测试基类配置

@SpringBootTest
@Transactional
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)
public class BaseTest {@Autowiredprotected UserService userService;@Autowiredprotected UserMapper userMapper;
}

2. 完整测试类 UserServiceTest.java

class UserServiceTest extends BaseTest {@Testvoid testCRUD() {// 创建测试User newUser = new User(null, "张三", 25, null);int insertResult = userService.createUser(newUser);assertEquals(1, insertResult);assertNotNull(newUser.getId());// 查询测试User fetchedUser = userService.getUserById(newUser.getId());assertEquals("张三", fetchedUser.getName());assertEquals(25, fetchedUser.getAge());// 更新测试fetchedUser.setAge(26);int updateResult = userService.updateUser(fetchedUser);assertEquals(1, updateResult);User updatedUser = userService.getUserById(fetchedUser.getId());assertEquals(26, updatedUser.getAge());// 删除测试int deleteResult = userService.deleteUser(newUser.getId());assertEquals(1, deleteResult);User deletedUser = userService.getUserById(newUser.getId());assertNull(deletedUser);}
}

五、关键问题解决方案

1. 数据库连接问题

# 如果出现时区错误，在连接URL中添加：
spring.datasource.url: jdbc:mysql://localhost:3306/testdb?serverTimezone=Asia/Shanghai

2. MyBatis注解与XML配置选择

• 简单SQL使用注解方式
• 复杂SQL推荐XML配置（resources/mapper/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.shuanglibi.demo.mapper.UserMapper"><select id="findByName" resultType="User">SELECT * FROM user WHERE name = #{name}</select>
</mapper>

3. 事务管理配置

@Configuration
@EnableTransactionManagement
public class MyBatisConfig {// 可自定义事务管理器
}

六、运行与验证

1. 启动测试类执行所有测试方法
2. 查看控制台输出：

2023-10-20 14:30:22.123  INFO 12345 --- [           main] c.e.d.s.UserServiceTest                  : Started UserServiceTest in 2.345 seconds
2023-10-20 14:30:22.456  INFO 12345 --- [           main] o.s.t.c.transaction.TransactionContext   : Began transaction...

七、扩展建议

1. 添加分页查询：使用PageHelper插件
2. 集成Swagger文档：

<dependency><groupId>io.springfox</groupId><artifactId>springfox-boot-starter</artifactId><version>3.0.0</version>
</dependency>

3. 使用MyBatis Generator自动生成代码：

<plugin><groupId>org.mybatis.generator</groupId><artifactId>mybatis-generator-maven-plugin</artifactId><version>1.4.2</version>
</plugin>

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文章亮点：

1. 完整覆盖Spring Boot 2.x + MyBatis整合流程
2. 提供可直接运行的测试代码
3. 包含常见问题解决方案
4. 遵循Java 1.8语法规范
5. 使用现代测试框架（JUnit 5 + Spring Boot Test）

建议读者在实际操作时注意：
6. 提前创建好testdb数据库
7. 保持MySQL服务正常运行
8. 根据实际情况修改数据库连接参数
9. 使用Postman进行接口验证（配合Controller层）

源码在此，插去直接可以用，记得耐心点等待依赖下载完再启动。 （Spring Boot整合MyBatis+MySQL源码）