爆出异常，不知原因！

Caused by: org.springframework.beans.factory.BeanDefinitionStoreException: Failed to read candidate component class: file [E:\demo\target\classes\com\imooc\demo\config\dao\DataSourceConfiguration.class]; nested exception is java.lang.annotation.AnnotationFormatError: Invalid default: public abstract java.lang.Class org.mybatis.spring.annotation.MapperScan.factoryBean()