【Mybatis-Plus】Spring整合 驼峰命名设置失效问题

查询时发现这个问题：

DEBUG [main] - Creating a new SqlSession
DEBUG [main] - SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@4ef74c30] was not registered for synchronization because synchronization is not active
DEBUG [main] - Fetching JDBC Connection from DataSource
DEBUG [main] - Creating new JDBC DriverManager Connection to [jdbc:mysql://localhost:3306/oa?serverTimezone=GMT]
DEBUG [main] - JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@319bc845] will not be managed by Spring
DEBUG [main] - ==>  Preparing: SELECT user_id,user_name,user_password,user_status,user_is_del FROM sys_user WHERE user_id=?
DEBUG [main] - ==> Parameters: 3(Integer)
DEBUG [main] - <==      Total: 1
DEBUG [main] - Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@4ef74c30]
null

我们的User实体类完全符合表字段名称，一模一样

到这里我就多半猜到是驼峰自动匹配了，数据库表字段是ab_cdef_ghij这样的命名规范的

Mybatis-Plus直接给Java转换成abCdefGhij这样了

找不到关于MybatisPlus在Spring中是如何取消驼峰配置的，可以做的是改变实体类属性为驼峰符合的命名：

再次测试的结果：

DEBUG [main] - Creating a new SqlSession
DEBUG [main] - SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7d61eb55] was not registered for synchronization because synchronization is not active
DEBUG [main] - Fetching JDBC Connection from DataSource
DEBUG [main] - Creating new JDBC DriverManager Connection to [jdbc:mysql://localhost:3306/oa?serverTimezone=GMT]
DEBUG [main] - JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@58ffcbd7] will not be managed by Spring
DEBUG [main] - ==>  Preparing: SELECT user_id,user_name,user_password,user_status,user_is_del FROM sys_user WHERE user_id=?
DEBUG [main] - ==> Parameters: 3(Integer)
DEBUG [main] - <==      Total: 1
DEBUG [main] - Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7d61eb55]
User(userId=3, userName=user02, userPassword=123456, userStatus=1, userIsDel=0)

终于在百度各种博客帖子查不到我想要的答案之后，直奔官方文档的解释查看：

https://mp.baomidou.com/config/#configuration

也就是说我需要使用原生Mybatis的XML文件来配置

上面的注解@TableField也不需要

然后再往上翻，基本配置中找到了：

可是我就算这样配置了也照样没用啊？？？

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"

       xsi:schemaLocation="
       http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd

       http://www.springframework.org/schema/context
       http://www.springframework.org/schema/context/spring-context.xsd
"
>
    <!--
        dao层的配置：核心是要产生
        Mapper代理类对象
        1.引入数据库配置信息
        2.数据源配置
        3.SqlSessionFactory
        4.产生Mapper接口的代理类对象
    -->

    <!-- 1.引入数据库配置信息 -->
    <context:property-placeholder location="classpath:db.properties" system-properties-mode="FALLBACK" />

    <!--2.数据源配置 -->
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="${jdbc.driverClassName}" />
        <property name="url" value="${jdbc.url}" />
        <property name="username" value="${jdbc.username}" />
        <property name="password" value="${jdbc.password}" />
    </bean>

    <!-- 3.SqlSessionFactory -->
    <bean id="sqlSessionFactory" class="com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean">

        <property name="dataSource" ref="dataSource" />
        <property name="globalConfig" ref="globalConfig" />
        <property name="configuration" ref="configuration" />

        <!-- 加载xxMapper.xml -->
        <property name="mapperLocations">
            <array>
                <value>classpath:mybatis/mapper/*Mapper.xml</value>
            </array>
        </property>

        <!-- 配置分页插件 -->
        <property name="plugins">
            <array>
                <bean class="com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor"/>
            </array>
        </property>
    </bean>

    <bean id="configuration" class="com.baomidou.mybatisplus.core.MybatisConfiguration">
       <property name="mapUnderscoreToCamelCase" value="false" />
    </bean>

    <!-- 声明全局配置 -->
    <bean id="globalConfig" class="com.baomidou.mybatisplus.core.config.GlobalConfig">
        <!-- 指定主键自动增长类型 -->
        <property name="dbConfig" ref="dbConfig" />
    </bean>

    <bean id="dbConfig" class="com.baomidou.mybatisplus.core.config.GlobalConfig.DbConfig">
        <property name="idType" value="AUTO" />
    </bean>

    <!-- 4.产生Mapper接口的代理类对象 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!-- 需要生成代理类对象的mapper接口包 -->
        <property name="basePackage" value="cn.echo42.mapper" />
        <!-- sqlSessionFactory 的name 用于为代理类中生成SqlSession -->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />
    </bean>
</beans>

测试结果：

DEBUG [main] - Creating a new SqlSession
DEBUG [main] - SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7d61eb55] was not registered for synchronization because synchronization is not active
DEBUG [main] - Fetching JDBC Connection from DataSource
DEBUG [main] - Creating new JDBC DriverManager Connection to [jdbc:mysql://localhost:3306/oa?serverTimezone=GMT]
DEBUG [main] - JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@58ffcbd7] will not be managed by Spring
DEBUG [main] - ==>  Preparing: SELECT user_id,user_name,user_password,user_status,user_is_del FROM sys_user WHERE user_id=?
DEBUG [main] - ==> Parameters: 3(Integer)
DEBUG [main] - <==      Total: 1
DEBUG [main] - Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7d61eb55]
null

暂时使用驼峰规则来使用了。。。