Springboot整合mybatis配置多数据源

1.自定义动态数据源类继承AbstractRoutingDataSouce类，并创建一个ThreadLocal变量，用于设置或者获取当前数据源的key

2.实现determineCurrentLookupKey()方法，此方法用于确定当前数据源的key，以选择对应的数据源。

3.将多数据源封装到targetDataSources对象中，并指定默认数据源

4.将自定义数据源绑定到SqlSessionFactoryBean实例上；

5.自定义切面对需要的方法进行拦截，并设置数据源的key

 

具体相关示例代码如下：

public class DynamicDataSource extends AbstractRoutingDataSource {

    public static final String DB1_DATA_SOURCE = "db1DataSource";
    public static final String DB2_DATA_SOURCE = "db2DataSource";

    private static final ThreadLocal<String> CURRENT_DATA_SOURCE = new ThreadLocal<>();

    /**
     * 设置当前数据源
     * @param dataSourceName
     */
    public static void setDataSource(String dataSourceName) {
        CURRENT_DATA_SOURCE.set(dataSourceName);
    }

    public static String getDataSource(){
        return CURRENT_DATA_SOURCE.get();
    }
    @Override
    protected Object determineCurrentLookupKey() {
        String dataSource = CURRENT_DATA_SOURCE.get();
        if(StringUtils.isEmpty(dataSource)){
            return DB1_DATA_SOURCE;
        }
        return dataSource;
    }
}

    @Bean
    public DynamicDataSource dataSource(
            @Qualifier(DynamicDataSource.DB1_DATA_SOURCE) DataSource db1DataSource,
            @Qualifier(DynamicDataSource.DB2_DATA_SOURCE) DataSource db2DataSource){

        // logger.info("配置动态数据源：db1DataSource:{},db2DataSource:{}",db1DataSource,db2DataSource);
        DynamicDataSource dynamicDataSource = new DynamicDataSource();
        Map<Object,Object> targetDataSources = new HashMap<>();
        targetDataSources.put(DynamicDataSource.DB1_DATA_SOURCE,db1DataSource);
        targetDataSources.put(DynamicDataSource.DB2_DATA_SOURCE,db2DataSource);
        dynamicDataSource.setDefaultTargetDataSource(db1DataSource);
        dynamicDataSource.setTargetDataSources(targetDataSources);
        dynamicDataSource.afterPropertiesSet();
        return dynamicDataSource;
    }

    @Bean
    public SqlSessionFactoryBean sqlSessionFactoryBean(DynamicDataSource dynamicDataSource) throws IOException {
        logger.info("配置SqlSessionFactoryBean：{}",dynamicDataSource.determineCurrentLookupKey());
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();
        configuration.setLogImpl(StdOutImpl.class);
        configuration.setMapUnderscoreToCamelCase(true);
        configuration.setCallSettersOnNulls(true);
        sqlSessionFactoryBean.setConfiguration(configuration);
        sqlSessionFactoryBean.setDataSource(dynamicDataSource);
        ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        sqlSessionFactoryBean.setMapperLocations(resolver.getResources(mapperLocations));
        return sqlSessionFactoryBean;
    }

 

如果多数据源中如果除了纯db连接配置还有JNDI的数据源，可以对数据源做如下处理

    @Primary
    @Bean(name = DynamicDataSource.DB1_DATA_SOURCE)
    @ConfigurationProperties(prefix = DB1_DATA_SOURCE_PREFIX)
    public DataSource db1DataSource() throws NamingException {
        String jndiName = jndi1DataSource.getJndiName();
        if (!StringUtils.isEmpty(jndiName)){
            logger.info("db1DataSource使用的JNDI数据源");
            return jndiDataSource(jndiName);
        }
        return DataSourceBuilder.create().build();
    }

 如果不需要做动态数据源，而是固定多数据源的情况，直接配置两个sqlSessionFactory，每个SqlSessionFactory指定自己的配置，代码示例如下：

@Configuration
@Slf4j
@MapperScan(basePackages = "com.xxx.xxx.dao.xxx",sqlSessionFactoryRef = "sqlSessionFactory2")
public class DataSourceConfig {

    @Value("${mybatis.mapper-locations}")
    private String mapperLocations;

    @Bean(name = "db2DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.db2")
    public DataSource db2DataSource(){
        return DataSourceBuilder.create().build();
    }

    @Bean
    public DataSourceTransactionManager transactionManager2(DataSource db2DataSource){
        return new DataSourceTransactionManager(db2DataSource);
    }

    @Bean
    public SqlSessionFactory sqlSessionFactory2(DataSource db2DataSource) throws Exception {
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();
        configuration.setLogImpl(StdOutImpl.class);
        configuration.setMapUnderscoreToCamelCase(true);
        configuration.setCallSettersOnNulls(true);
        sqlSessionFactoryBean.setConfiguration(configuration);
        sqlSessionFactoryBean.setDataSource(db2DataSource);
        ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        sqlSessionFactoryBean.setMapperLocations(resolver.getResources(mapperLocations));
        return sqlSessionFactoryBean.getObject();
    }
}

注：以上方式可以保证不同数据源拥有自己的事务管理器，如果是动态数据源，即使配置多个事务管理器也不生效。