1.问题描述

mysql数据字段表

id             int(11)
user_name      varchar(45)
user_age       varchar(45)

spring-boot中的Entity

public class UserEntity {
    private Integer  id;
    private String  userName;
    private String userAge;
}

application.yml中配置

# 下划线自动映射小驼峰
mybatis:
  configuration:
    map-underscore-to-camel-case: true

正常情况下做了自动映射配置,做全量查询(select * from talbe)操作时mybatis会将下划线字段映射到小驼峰属性。但是由于配置了多数据源导致此项配置没有生效.

project--|
         |-src
         |-main--|
                 |-java.com.xxx--|
                                 |-config--|
                                           |-MysqlServerConfig
                                           |-xxServerConfig
                                 |-controller
                                 |-entity

其中的MysqlServerConfig和xxServerConfig为两个数据源,下面已MysqlServerConfig为例
MysqlServerConfig中因种种原因不能上源码，故从大佬哪里copy了一份原文地址:https://blog.csdn.net/qq_32512453/article/details/113752810

// “com.zhxd.mysql.mapper”这里需要注意mysql和taosdb的目录是不同的
@Configuration
@MapperScan(basePackages = {"com.zhxd.mysql.mapper"},sqlSessionFactoryRef = "mysqlSqlSessionFactory")
//这里一定要注意，这个basePackages是你的mapper接口及service所在的包名，
// 而下面的红线所标注的classpath是mapper.xml所在的位置，这个xml是配置文件，
// 处在resources里，他的路径也要格外区分开。
public class MySqlConfiguration {
 
    @Bean(name="mysqlDataSource")
    //下面的注解作用就是从application.properties中读取以这个字符串开头的那些配置，设置为数据源的配置
    @ConfigurationProperties(prefix ="spring.datasource.mysql")
    public DataSource mysqlDataSource(){
        return DataSourceBuilder.create().build();
    }
    @Bean(name="mysqlSqlSessionFactory")
    public SqlSessionFactory mysqlSqlSessionFactory(@Qualifier("mysqlDataSource") DataSource dataSource)throws Exception{
        SqlSessionFactoryBean bean=new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        // 这里配置的是mysql需要读取的xml文件路径
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/mysql/*Mapper.xml"));
        SqlSessionFactory sqlSessionFactory = bean.getObject();
        return sqlSessionFactory;
    }
    @Bean(name = "mysqlTransactionManager")
    public DataSourceTransactionManager mysqlTransactionManager(@Qualifier("mysqlDataSource")DataSource dataSource){
        return new DataSourceTransactionManager(dataSource);
    }
    @Bean(name="mysqlSqlSessionTemplate")
    public SqlSessionTemplate mysqlSqlSessionTemplate(@Qualifier("mysqlSqlSessionFactory")SqlSessionFactory sqlSessionFactory){
        return new SqlSessionTemplate(sqlSessionFactory);
    }
 
}

2.问题刨析

因为在多数据源中自定义的sqlsessionFactory导致了不会加载yml文件所以mybatis的配置也就不会生效了。

3.问题解决

更新后的MysqlServerConfig

@Configuration
@MapperScan(basePackages = {"com.zhxd.mysql.mapper"},sqlSessionFactoryRef = "mysqlSqlSessionFactory")
public class MySqlConfiguration {

    // 配置一个全局配置方法
    @Bean
    @ConfiguraitonProperties(prefix = "mybatis.configuration")
    public org.apache.ibatis.session.Configuration globalConfiguration(){
         return new org.apche.ibatis.session.Configuration();
    }


    @Bean(name="mysqlDataSource")
    @ConfigurationProperties(prefix ="spring.datasource.mysql")
    public DataSource mysqlDataSource(){
        return DataSourceBuilder.create().build();
    }
    @Bean(name="mysqlSqlSessionFactory")
    public SqlSessionFactory mysqlSqlSessionFactory(@Qualifier("mysqlDataSource") DataSource dataSource)throws Exception{
        SqlSessionFactoryBean bean=new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/mysql/*Mapper.xml"));
        // 将新对象加入bean
        bean.setConfiguration(globalConfiguration());
        SqlSessionFactory sqlSessionFactory = bean.getObject();
        return sqlSessionFactory;
    }
    @Bean(name = "mysqlTransactionManager")
    public DataSourceTransactionManager mysqlTransactionManager(@Qualifier("mysqlDataSource")DataSource dataSource){
        return new DataSourceTransactionManager(dataSource);
    }
    @Bean(name="mysqlSqlSessionTemplate")
    public SqlSessionTemplate mysqlSqlSessionTemplate(@Qualifier("mysqlSqlSessionFactory")SqlSessionFactory sqlSessionFactory){
        return new SqlSessionTemplate(sqlSessionFactory);
    }
 
}