springboot2+mybatis多种方式实现多数据配置方法

时间:2021-05-19

业务系统复杂程度增加,为了解决数据库I/O瓶颈,很自然会进行拆库拆表分服务来应对。这就会出现一个系统中可能会访问多处数据库,需要配置多个数据源。

第一种场景:项目服务从其它多处数据库取基础数据进行业务处理,因此各库之间不会出现重表等情况。

第二种场景:为了减轻写入压力进行读写分库,读走从库,写为主库。此种表名等信息皆为一致。

第三种场景:以上两种皆有。对于某些业务需要大数据量的汇总统计,希望不影响正常业务必须走从库(表信息一致),某些配置信息不存在读写压力,出现不分库(表信息不一致)

项目源代码:

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

有三个目录:

one:
直接使用多@Bean配置,@MapperScan来路径区分读何库

two:
使用注解的方式来标识走何dataSource,AOP拦截注入动态数据源

third:
使用spring的Bean命名策略进行区分数据来源

项目技术选型: 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新版本必须带有serverTimezone,不然会报连接异常。

第一种:通过@MapperScans 扫描匹配相关的数据源

@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); }}

第二种是动态数据源模式,通过AOP切入注解引导使用何数据源。用自定义注解@interface来标识方法走对应的数据源。

注意事项:类中的方法再调用带数据源的方法,不能被AOP切入

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

extends spring的动态DataSource路由来匹配

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会破坏相关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(); //设置数据源映射 dataSource.setTargetDataSources(targetDataSources);//// 设置默认数据源,当无法映射到数据源时会使用默认数据源 dataSource.setDefaultTargetDataSource(coreDataSource); dataSource.afterPropertiesSet(); return dataSource; } /** * 根据数据源创建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); }

第三种,自定义Bean命名策略,按beanName进行自动匹配使用数据源

@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自动扫描,将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,三种多数据源匹配主要点介绍完,详细直接下载github项目。 在resources/db含有相关测试表及数据脚本。

到此这篇关于springboot2+mybatis多种方式实现多数据配置方法的文章就介绍到这了,更多相关springboot2+mybatis 多数据内容请搜索以前的文章或继续浏览下面的相关文章希望大家以后多多支持!

声明:本页内容来源网络,仅供用户参考;我单位不保证亦不表示资料全面及准确无误,也不保证亦不表示这些资料为最新信息,如因任何原因,本网内容或者用户因倚赖本网内容造成任何损失或损害,我单位将不会负任何法律责任。如涉及版权问题,请提交至online#300.cn邮箱联系删除。

相关文章