Consider defining a bean of type '*Mapper' in your configuration.

pom.xml

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.0.1</version>
</dependency>

1.在Mapper接口上贴@Mapper

@Repository
@Mapper
public interface CommodityMapper {
    /**
     * 查询所有商品信息
     * @return List<Commodity> 所有商品信息
     */
    List<Commodity> selectAll();
}

2.启动类上贴@MapperScan(value = "com.xiami.springboot.sbootdemo.mapper")注解,告诉Spring,Mapper接口的位置

@SpringBootApplication
@MapperScan(value = "com.xiami.springboot.sbootdemo.mapper")
public class SbootdemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SbootdemoApplication.class, args);
    }

}