springboot mybatis 多数据源配置

首先导入mybatis等包，这里就不多说。

下面是配置多数据源和mybatis，每个数据源对应一套mybatis模板

数据源1：

 package com.aaaaaaa.config.datasource;

 import javax.sql.DataSource;

 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.beans.factory.annotation.Qualifier;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Primary;
 import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
 import org.springframework.jdbc.datasource.DataSourceTransactionManager;

 /**
  *
  * @desc 支持多数据源配置，复制一份代码修改所有appdb即可<br>
  *       以该数据源为主数据源。只能设置@Primary到一份数据源作为主数据源
  * @author josnow
  * @date 2018年1月12日 下午9:58:18
  * @version 1.0.0
  */
 @Configuration
 @MapperScan(basePackages = "com.aaaaaaa.mapper.appdb", sqlSessionTemplateRef = "appdbSqlSessionTemplate")
 public class DataSourceConfigappdb {

     @Bean(name = "appdbDataSource")
     @ConfigurationProperties(prefix = "spring.datasource.appdb")
     @Primary
     public DataSource testDataSource() {
         return DataSourceBuilder.create().build();
     }

     @Bean(name = "appdbSqlSessionFactory")
     @Primary
     public SqlSessionFactory testSqlSessionFactory(@Qualifier("appdbDataSource") DataSource dataSource)
             throws Exception {
         SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
         bean.setDataSource(dataSource);
         bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mapper/appdb/*.xml"));
         return bean.getObject();
     }

     @Bean(name = "appdbTransactionManager")
     @Primary
     public DataSourceTransactionManager testTransactionManager(@Qualifier("appdbDataSource") DataSource dataSource) {
         return new DataSourceTransactionManager(dataSource);
     }

     @Bean(name = "appdbSqlSessionTemplate")
     @Primary
     public SqlSessionTemplate testSqlSessionTemplate(
             @Qualifier("appdbSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
         return new SqlSessionTemplate(sqlSessionFactory);
     }

 }

application.yml配置

spring:
  datasource:
    appdb:
      driverClassName: com.mysql.jdbc.Driver
      url: jdbc:mysql://********:3306/******?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true
      username: ********
      password: ********
      initialSize: 5
      minIdle: 5
      maxActive: 20
      testWhileIdle: true
      validationQuery: select 1
      filters: stat,wall,log4j

就这样配置完了第一个数据源和mybatis。

第一个数据源由appdbTransactionManager来管理事务，在使用事务的时候用@Transactional(value = "appdbTransactionManager")注解来表明使用哪个事务管理器。

这里并未采用分布式事务管理器，分布式事务管理器是个大话题，如果你考虑分布式事务可以自己改造。

下面进行第二个数据源和mybatis的配置

 package com.aaaaaaa.config.datasource;

 import javax.sql.DataSource;

 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.beans.factory.annotation.Qualifier;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
 import org.springframework.boot.context.properties.ConfigurationProperties;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
 import org.springframework.jdbc.datasource.DataSourceTransactionManager;

 @Configuration
 @MapperScan(basePackages = "com.aaaaaaa.mapper.testdb", sqlSessionTemplateRef = "testdbSqlSessionTemplate")
 public class DataSourceConfigtestdb {

     @Bean(name = "testdbDataSource")
     @ConfigurationProperties(prefix = "spring.datasource.testdb")
     public DataSource testDataSource() {
         return DataSourceBuilder.create().build();
     }

     @Bean(name = "testdbSqlSessionFactory")
     public SqlSessionFactory testSqlSessionFactory(@Qualifier("testdbDataSource") DataSource dataSource)
             throws Exception {
         SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
         bean.setDataSource(dataSource);
         bean.setMapperLocations(
                 new PathMatchingResourcePatternResolver().getResources("classpath:mapper/testdb/*.xml"));
         return bean.getObject();
     }

     @Bean(name = "testdbTransactionManager")
     public DataSourceTransactionManager testTransactionManager(@Qualifier("testdbDataSource") DataSource dataSource) {
         return new DataSourceTransactionManager(dataSource);
     }

     @Bean(name = "testdbSqlSessionTemplate")
     public SqlSessionTemplate testSqlSessionTemplate(
             @Qualifier("testdbSqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
         return new SqlSessionTemplate(sqlSessionFactory);
     }

 }

数据源2的配置

application.yml配置

spring:
  datasource:
    appdb:
      driverClassName: com.mysql.jdbc.Driver
      url: jdbc:mysql://********:3306/******?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true
      username: ********
      password: ********
      initialSize: 5
      minIdle: 5
      maxActive: 20
      testWhileIdle: true
      validationQuery: select 1
      filters: stat,wall,log4j
    testdb:
      driverClassName: com.mysql.jdbc.Driver
      url: jdbc:mysql://********:3306/******?useUnicode=true&characterEncoding=UTF-8&zeroDateTimeBehavior=convertToNull&allowMultiQueries=true
      username: ********
      password: ********
      initialSize: 5
      minIdle: 5
      maxActive: 20
      testWhileIdle: true
      validationQuery: select 1
      filters: stat,wall,log4j

看一下两个数据源有哪些不同之处：

1：数据源2其实是由数据源1copy了一份代码，并将全部appdb改为testdb

2：此外数据源1有@Primary注解，而数据源2没有@Primary注解。使用@Primary注解是将数据源1作为默认数据源，并且多个数据源必须指定一个默认的数据源，否则会启动报错。

mybatis多数据源就是这么简单