（18）spring boot整合mybatis

迈不过友情╰ 2022-02-03 15:47 156阅读 0赞

分为全注解版和配置版。

其实全注解版比较简单。

# 全注解版 #

1.在配置文件中配置数据源信息 ，注意，根据需要可以开启驼峰映射（一般选择开启）

spring.datasource.url=jdbc:mysql://localhost:3306/spring_cache
    spring.datasource.username=root
    spring.datasource.password=
    spring.datasource.driver-class-name=com.mysql.jdbc.Driver
    #开启驼峰映射
    mybatis.configuration.map-underscore-to-camel-case=true
    logging.level.com.jiangyi.springboot01cache.mapper=debug

2.使用注解版的mybatis
            1.使用@MapperScan()来扫描包。在主运行类上使用。

@MapperScan("com.jiangyi.springboot01cache.mapper")
    @SpringBootApplication
    @EnableCaching
    public class SpringBoot01CacheApplication {
    
        public static void main(String[] args) {
            SpringApplication.run(SpringBoot01CacheApplication.class, args);
        }
    
    }

3.创建包：**使用@Mapper 注解来标志：**

@Mapper
    public interface EmployeeMapper {
        @Select("select * from employee where id=#{id}")
        public Employee getEmpById(Integer id);
    
        @Update("update employee set lastName=#{lastName},email=#{email},gender=#{gender},id=#{dId} where id=#{id}")
        public void updateEmp(Employee employee);
    
        @Delete("delete from employee where id=#{id}")
        public void deleteEmpById(Integer id);
    
        @Insert("insert into employee(lastName,email,gender,d_id) values(#{lastName},#{email},#{gender},#{dId})")
        public void insertEmployee(Employee employee);
    }

4.创建service：

@Service
    public class EmployeeService {
        @Autowired
        EmployeeMapper employeeMapper;
    
        @Cacheable(cacheNames = {"emp"})
        public Employee getEmp(Integer id){
            System.out.println("查询"+id+"号员工");
            Employee emp = employeeMapper.getEmpById(id);
            return emp;
        }
    }

后面就可以直接调用service里面的方法来与数据库交互了。

# 使用配置文件 #

去github上搜索mybatis，可以看到配置xml文件的模板。也可以去我的博客上有归纳。

创建相关的：

![20190509194707125.png][]

employeeMapper.xml:

<!DOCTYPE mapper
    
            PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
    
            "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
    
    <mapper namespace="com.jiangyi.springboot06.mapper.EmployeeMapper">
    
        
    
        <select id="getEmpById" resultType="com.jiangyi.springboot06.bean.Employee">
    
            select * from employee where id=#{id}
    
        </select>
    
    
    
        <insert id="insertEmp">
    
            insert into employee(lastName,email,gender,d_id) values (#{lastName},#{email},#{gender},#{dId})
    
        </insert>
    
    
    
    </mapper>

mybatis-config.xml:

<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
    
    <configuration>
    
    <settings>
    
        
    
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    
    </settings>
    
    </configuration>

当然在yaml配置文件里面也需要配置；

mybatis:
    
      config-location: classpath:mybatis/mybatis-config.xml
    
      mapper-locations: classpath:mybatis/mapper/*.xml

OK了。。。。。。。。。。。。。。。。。。。。

[20190509194707125.png]: /images/20220203/6565c994ded64218a8392db81ce46970.png