springboot项目启动时出现：TypeException: The alias 'XXX' is already mapped to the value 'XX' 错误

ゝ一世哀愁。 2024-04-18 15:48 1阅读 0赞

springboot项目启动时具体报错内容如下：

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'accountController': Unsatisfied dependency expressed through field 'accountService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'accountServiceImpl': Unsatisfied dependency expressed through field 'accountDAO'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'accountDAO' defined in file \[F:\\gov-meeting\\meeting\_base\\meeting\_server\\target\\classes\\com\\zkml\\meeting\_base\\server\\dao\\AccountDAO.class\]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource \[org/mybatis/spring/boot/autoconfigure/MybatisAutoConfiguration.class\]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate \[org.apache.ibatis.session.SqlSessionFactory\]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.apache.ibatis.type.TypeException: The alias 'BoardConfigInput' is already mapped to the value 'com.zkml.meeting\_base.client.input.order.BoardConfigInput'.

这个错是因为mybatis的配置模糊造成的，下面的com.zkml.meeting\_base意思是扫描这个路径下的po、DAO等，但是看项目工程目录，client层和server层都是这个路径，这样mybatis就会对这两个层都扫描，当出现重复map的类时就会报这个错。如下是项目的mybatis别名路径设置和项目工程目录情况：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70 1][]

上面的目录中这个com.zkml.meeting\_base为server层和client层共有。解决办法就是把这个路径范围缩小，写得更具体一些，这里po、DAO等都在server层，因此只需要扫描server层即可，配置修改如下：

![20190909111618257.png][]

修改后项目正常启动

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/72022be957e548668d4ee53d41c081b2.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MTIzMTkyOA_size_16_color_FFFFFF_t_70 1]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/fb8f8e613db043a592c678c795c53d2a.png
[20190909111618257.png]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/df1af2eae1d54fe2a1e5468387093d52.png