springboot + mybatis 多数据源

springboot + mybatis 多数据源

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测试：多个mysql连接，使用Druid连接池

1.依赖 ，druid,web,lombok,mysql,mybatis

 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.0</version>
        </dependency>

        <!--Druid-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
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2.application.properties 配置两个数据源

#mysql
spring.datasource.one.url=jdbc:mysql://localhost:3306/test?serverTimezone=UTC
spring.datasource.one.username=root
spring.datasource.one.password=
spring.datasource.one.type=com.alibaba.druid.pool.DruidDataSource

spring.datasource.two.url=jdbc:mysql://localhost:3306/workflow?serverTimezone=UTC
spring.datasource.two.username=root
spring.datasource.two.password=
spring.datasource.two.type=com.alibaba.druid.pool.DruidDataSource
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3.配置两个数据源和两个mapper

MybatisConfigOne .java

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

import javax.annotation.Resource;
import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.mybatis.demo.mapper.mapper1", sqlSessionFactoryRef = "sqlSessionFactoryOne", sqlSessionTemplateRef = "sqlSessionTemplateOne")
public class MybatisConfigOne {

    @Resource(name = "dsOne")
    DataSource dsOne;

    @Bean
    SqlSessionFactory sqlSessionFactoryOne() {
        SqlSessionFactory sessionFactory = null;
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dsOne);
        //添加驼峰映射
        org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();
        configuration.setMapUnderscoreToCamelCase(true);
        bean.setConfiguration(configuration);
        try {
            sessionFactory = bean.getObject();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return sessionFactory;
    }

    @Bean
    SqlSessionTemplate sqlSessionTemplateOne() {
        return new SqlSessionTemplate(sqlSessionFactoryOne());
    }
}
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MybatisConfigOne .java

import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.annotation.Resource;
import javax.sql.DataSource;

@Configuration
@MapperScan(basePackages = "com.mybatis.demo.mapper.mapper2", sqlSessionFactoryRef = "sqlSessionFactoryTwo", sqlSessionTemplateRef = "sqlSessionTemplateTwo")
public class MybatisConfigTwo {

    @Resource(name = "dsTwo")
    DataSource dsTwo;

    @Bean
    SqlSessionFactory sqlSessionFactoryTwo() {
        SqlSessionFactory sessionFactory = null;
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dsTwo);
        //添加驼峰映射
        org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();
        configuration.setMapUnderscoreToCamelCase(true);
        bean.setConfiguration(configuration);
        try {
            sessionFactory = bean.getObject();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return sessionFactory;
    }

    @Bean
    SqlSessionTemplate sqlSessionTemplateTwo() {
        return new SqlSessionTemplate(sqlSessionFactoryTwo());
    }
}
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两个mapper 一样放在不同目录下

import com.mybatis.demo.domain.Test;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;

@Mapper
public interface TestDao1 {
//public interface TestDao2 {
    @Select("select * from mybatis")
    List<Test> listTest();

}
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4.调用可查询出数据，ok

5.其他问题：

1）多数据源下，驼峰映射不生效，字段为null

多数据源时，spring不知道为哪个数据源开启驼峰命名,配置数据源时手动添加，如下

  @Bean
    SqlSessionFactory sqlSessionFactoryOne() {
        SqlSessionFactory sessionFactory = null;
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dsOne);
        //添加驼峰映射
        org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();
        configuration.setMapUnderscoreToCamelCase(true);
        bean.setConfiguration(configuration);
        try {
            sessionFactory = bean.getObject();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return sessionFactory;
    }
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2）不使用druid连接池，使用springboot自带的Hikari 连接池
无需引入druid依赖，配置url时写jdbc-url,不然会报找不到dataSource 错误。

@Configuration
public class DataSourceConfig {

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.one")
    DataSource dsOne() {
//        return DruidDataSourceBuilder.create().build();
        return DataSourceBuilder.create().build();

    }

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.two")
    DataSource dsTwo() {
//        return DruidDataSourceBuilder.create().build();
        return DataSourceBuilder.create().build();
    }
}
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