SpringBoot系列十九：整合Mybatis

àì夳堔傛蜴生んèń 2022-10-01 10:44 296阅读 0赞

1、引入依赖

<dependency>
    	<groupId>org.mybatis.spring.boot</groupId>
    	<artifactId>mybatis-spring-boot-starter</artifactId>
    	<version>1.3.1</version>
    </dependency>

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpemhpcWlhbmcxMjE3_size_16_color_FFFFFF_t_70]  
2、注解版

@Mapper
    public interface DepartmentMapper {
    
        @Select("select * from department where id=#{id}")
        public Department getDeptById(Integer id);
    
        @Delete("delete from department where id=#{id}")
        public int deleteDeptById(Integer id);
    
        @Options(useGeneratedKeys = true,keyProperty = "id")
        @Insert("insert into department(departmentName) values(#{departmentName})")
        public int insertDept(Department department);
    
        @Update("update department set departmentName=#{departmentName} where id=#{id}")
        public int updateDept(Department department);
    }

MyBatis配置类：给容器中添加一个ConfigurationCustomizer。

@org.springframework.context.annotation.Configuration
    public class MyBatisConfig {
    
        @Bean
        public ConfigurationCustomizer configurationCustomizer(){
            return new ConfigurationCustomizer(){
    
                @Override
                public void customize(Configuration configuration) {
                	//开启驼峰命名法
                    configuration.setMapUnderscoreToCamelCase(true);
                }
            }
        }
    }

使用 @MapperScan 批量扫描所有的Mapper接口；这样就不需要在每个Mapper接口上添加 @Mapper 注解。

@MapperScan(value = "com.atguigu.springboot.mapper")
    @SpringBootApplication
    public class SpringBoot06DataMybatisApplication {
    
    	public static void main(String[] args) {
    		SpringApplication.run(SpringBoot06DataMybatisApplication.class, args);
    	}
    }

3、配置文件版。参照：[http://www.mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/][http_www.mybatis.org_spring-boot-starter_mybatis-spring-boot-autoconfigure]

//@Mapper或者@MapperScan将接口扫描装配到容器中
    public interface EmployeeMapper {
    
        public Employee getEmpById(Integer id);
    
        public void insertEmp(Employee employee);
    }

（1）、在yml中配置

mybatis:
      config-location: classpath:mybatis/mybatis-config.xml 指定全局配置文件的位置
      mapper-locations: classpath:mybatis/mapper/*.xml  指定sql映射文件的位置

（2）、Mybatis全局配置文件 mybatis-config.xml

<?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>
    
        <settings>
        	
            <setting name="mapUnderscoreToCamelCase" value="true"/>
        </settings>
    </configuration>

（3）、Mapper映射文件 EmployeeMapper.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.atguigu.springboot.mapper.EmployeeMapper">
       
        <select id="getEmpById" resultType="com.atguigu.springboot.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>

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpemhpcWlhbmcxMjE3_size_16_color_FFFFFF_t_70]: /images/20220118/bc916702969e4b3eae293aeac20b933f.png
[http_www.mybatis.org_spring-boot-starter_mybatis-spring-boot-autoconfigure]: http://www.mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/