SpringBoot启动报错
 

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APPLICATION FAILED TO START
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Description:

Field helloWordService in com.example.demo.controller.HelloWord required a bean of type 'com.example.demo.dao.HelloWordDao' that could not be found.

The injection point has the following annotations:
    - @org.springframework.beans.factory.annotation.Autowired(required=true)

Action:

Consider defining a bean of type 'com.example.demo.dao.HelloWordDao' in your configuration.

Process finished with exit code 1

1:在Dao层中加上@Mapper注解 之后继承  BaseMapper 类

2：在yml文件引入依赖

#mybatis
mybatis-plus:
  mapper-locations: classpath*:com/zhangtao/moguding/*/dao/mapper/*.xml
  #实体扫描，多个package用逗号或者分号分隔
  typeAliasesPackage: com.zhangtao.moguding.*.dto
  configuration:
        #配置返回数据库(column下划线命名&&返回java实体是驼峰命名)，自动匹配无需as（没开启这个，SQL需要写as： select user_id as userId）
        map-underscore-to-camel-case: true
        cache-enabled: false
        #配置JdbcTypeForNull, oracle数据库必须配置
        jdbc-type-for-null: 'null'

3：在启动类加上@MapperScan注解

MapperScan(value = "com.example.demo.dao")*/