業務系統復雜程度增加，為了解決數據庫I/O瓶頸，很自然會進行拆庫拆表分服務來應對。這就會出現一個系統中可能會訪問多處數據庫，需要配置多個數據源。

第一種場景：項目服務從其它多處數據庫取基礎數據進行業務處理，因此各庫之間不會出現重表等情況。

第二種場景：為了減輕寫入壓力進行讀寫分庫，讀走從庫，寫為主庫。此種表名等信息皆為一致。

第三種場景：以上兩種皆有。對于某些業務需要大數據量的匯總統計，希望不影響正常業務必須走從庫（表信息一致），某些配置信息不存在讀寫壓力，出現不分庫（表信息不一致）

項目源代碼：

https://github.com/zzsong/springboot-multiple-datasource.git

有三個目錄：

one: 直接使用多@Bean配置，@MapperScan來路徑區分讀何庫

two: 使用注解的方式來標識走何dataSource,AOP攔截注入動態數據源

third: 使用spring的Bean命名策略進行區分數據來源

項目技術選型： springBoot2.2.5 + mybatis + druid + mysql

先看主要的pom包

<parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.5.RELEASE</version> <relativePath/> </parent><dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-aop</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.2</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.19</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid-spring-boot-starter</artifactId> <version>1.1.21</version> </dependency>

application.yml

spring: datasource: druid: core: url: jdbc:mysql:///kc_core?characterEncoding=utf-8&serverTimezone=Asia/Shanghai username: root password: 123456 driver-class-name: com.mysql.cj.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource schedule: url: jdbc:mysql:///kc_schedule?characterEncoding=utf-8&serverTimezone=Asia/Shanghai username: root password: 123456 driver-class-name: com.mysql.cj.jdbc.Driver type: com.alibaba.druid.pool.DruidDataSource

mysql新版本必須帶有serverTimezone，不然會報連接異常。

第一種：通過@MapperScans 掃描匹配相關的數據源

@Configuration@MapperScans({ @MapperScan(basePackages = 'com.zss.one.mapper.core', sqlSessionTemplateRef = 'coreSqlSessionTemplate',sqlSessionFactoryRef = 'coreSqlSessionFactory'), @MapperScan(basePackages = 'com.zss.one.mapper.schedule', sqlSessionTemplateRef = 'scheduleSqlSessionTemplate',sqlSessionFactoryRef = 'scheduleSqlSessionFactory')})public class MybatisOneConfig { @Bean @ConfigurationProperties(prefix = 'spring.datasource.druid.core') public DataSource coreDataSource(){ return DruidDataSourceBuilder.create().build(); } @Bean public SqlSessionFactory coreSqlSessionFactory(@Qualifier('coreDataSource') DataSource coreDataSource) throws Exception { SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean(); sessionFactory.setDataSource(coreDataSource); sessionFactory.getObject().getConfiguration().setJdbcTypeForNull(null); sessionFactory.getObject().getConfiguration().setMapUnderscoreToCamelCase(true); return sessionFactory.getObject(); } @Bean public SqlSessionTemplate coreSqlSessionTemplate(@Qualifier('coreSqlSessionFactory') SqlSessionFactory sqlSessionFactory) throws Exception { return new SqlSessionTemplate(sqlSessionFactory); } //======schedule======== @Bean @ConfigurationProperties(prefix = 'spring.datasource.druid.schedule') public DataSource scheduleDataSource(){ return DruidDataSourceBuilder.create().build(); } @Bean public SqlSessionFactory scheduleSqlSessionFactory(@Qualifier('scheduleDataSource') DataSource coreDataSource) throws Exception { SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean(); sessionFactory.setDataSource(coreDataSource); sessionFactory.getObject().getConfiguration().setJdbcTypeForNull(null); sessionFactory.getObject().getConfiguration().setMapUnderscoreToCamelCase(true); return sessionFactory.getObject(); } @Bean public SqlSessionTemplate scheduleSqlSessionTemplate(@Qualifier('scheduleSqlSessionFactory') SqlSessionFactory sqlSessionFactory) throws Exception { return new SqlSessionTemplate(sqlSessionFactory); }}

第二種是動態數據源模式，通過AOP切入注解引導使用何數據源。用自定義注解@interface來標識方法走對應的數據源。

注意事項：類中的方法再調用帶數據源的方法，不能被AOP切入

@Target({ElementType.METHOD, ElementType.TYPE})@Retention(RetentionPolicy.RUNTIME)@Documentedpublic @interface TargetDataSource { String value();}

extends spring的動態DataSource路由來匹配

public class DynamicDataSource extends AbstractRoutingDataSource { @Override protected Object determineCurrentLookupKey() { return DataSourceContextRouting.getDataSourceName(); }}

@Configuration//@EnableConfigurationProperties(MybatisProperties.class)//不要使用此公共配置，Configuration會破壞相關dataSource的配置@MapperScan('com.zss.two.mapper')public class MybatisConfig { @Bean @ConfigurationProperties(prefix = 'spring.datasource.druid.core') public DataSource coreDataSource() { return DruidDataSourceBuilder.create().build(); } @Bean @ConfigurationProperties(prefix = 'spring.datasource.druid.schedule') public DataSource scheduleDataSource() { return DruidDataSourceBuilder.create().build(); } @Autowired @Qualifier('coreDataSource') private DataSource coreDataSource; @Autowired @Qualifier('scheduleDataSource') private DataSource scheduleDataSource; @Bean public DynamicDataSource dataSource() { Map<Object, Object> targetDataSources = new HashMap<>(); targetDataSources.put(DataSourceConstants.CORE_DATA_SOURCE, coreDataSource); targetDataSources.put(DataSourceConstants.SCHEDULE_DATA_SOURCE, scheduleDataSource); DynamicDataSource dataSource = new DynamicDataSource(); //設置數據源映射 dataSource.setTargetDataSources(targetDataSources);//// 設置默認數據源，當無法映射到數據源時會使用默認數據源 dataSource.setDefaultTargetDataSource(coreDataSource); dataSource.afterPropertiesSet(); return dataSource; } /** * 根據數據源創建SqlSessionFactory */ @Bean public SqlSessionFactory sqlSessionFactory(DynamicDataSource dataSource) throws Exception { SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean(); sessionFactory.setDataSource(dataSource); sessionFactory.getObject().getConfiguration().setJdbcTypeForNull(null); sessionFactory.getObject().getConfiguration().setMapUnderscoreToCamelCase(true); return sessionFactory.getObject(); } @Bean public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) throws Exception { return new SqlSessionTemplate(sqlSessionFactory); }

第三種，自定義Bean命名策略，按beanName進行自動匹配使用數據源

@Componentpublic class CoreBeanNameGenerator implements BeanNameGenerator { @Override public String generateBeanName(BeanDefinition definition, BeanDefinitionRegistry registry) { return 'core'+ ClassUtils.getShortName(definition.getBeanClassName()); }}@Componentpublic class ScheduleBeanNameGenerator implements BeanNameGenerator { @Override public String generateBeanName(BeanDefinition definition, BeanDefinitionRegistry registry) { return 'schedule'+ ClassUtils.getShortName(definition.getBeanClassName()); }}

使用mybatis MapperScannerConfigurer自動掃描，將Mapper接口生成注入到spring

@Bean public MapperScannerConfigurer coreMapperScannerConfig(CoreBeanNameGenerator coreBeanNameGenerator){ MapperScannerConfigurer configurer = new MapperScannerConfigurer(); configurer.setNameGenerator(coreBeanNameGenerator); configurer.setBasePackage('com.zss.third.mapper.core,com.zss.third.mapper.order'); configurer.setSqlSessionFactoryBeanName('coreSqlSessionFactory'); configurer.setSqlSessionTemplateBeanName('coreSqlSessionTemplate'); return configurer; } @Bean public MapperScannerConfigurer scheduleMapperScannerConfig(ScheduleBeanNameGenerator scheduleBeanNameGenerator){ MapperScannerConfigurer configurer = new MapperScannerConfigurer(); configurer.setNameGenerator(scheduleBeanNameGenerator); configurer.setBasePackage('com.zss.third.mapper.schedule,com.zss.third.mapper.order'); configurer.setSqlSessionFactoryBeanName('scheduleSqlSessionFactory'); configurer.setSqlSessionTemplateBeanName('scheduleSqlSessionTemplate'); return configurer; }

到此，三種多數據源匹配主要點介紹完，詳細直接下載github項目。 在resources/db含有相關測試表及數據腳本。

到此這篇關于springboot2+mybatis多種方式實現多數據配置方法的文章就介紹到這了,更多相關springboot2+mybatis 多數據內容請搜索好吧啦網以前的文章或繼續瀏覽下面的相關文章希望大家以后多多支持好吧啦網！