SpringBoot Mybatis动态数据源切换方案实现过程

背景

最近让我做一个大数据的系统，分析了一下，麻烦的地方就是多数据源切换抽取数据。考虑到可以跨服务器跨数据库抽数，再整理数据，就配置了这个动态数据源的解决方案。在此分享给大家。

实现方案

数据库配置文件

我们项目使用的是yml形式的配置文件，采用的是hikari的数据库连接池。第一步我们自然是配置多个数据库源头。我们找到spring的datasource，在下方配置三个数据源。

spring: application: name: dynamicDatasource datasource: test1: driver-class-name: com.mysql.jdbc.Driver url: jdbc:mysql://127.0.0.1:3306/test1?serverTimezone=GMT%2B8&characterEncoding=utf-8&useSSL=false username: root password: 123456 test2: driver-class-name: com.mysql.jdbc.Driver url: jdbc:mysql://127.0.0.1:3306/test2?serverTimezone=GMT%2B8&characterEncoding=utf-8&useSSL=false username: root password: 123456 test3: driver-class-name: com.mysql.jdbc.Driver url: jdbc:mysql://127.0.0.1:3306/test3?serverTimezone=GMT%2B8&characterEncoding=utf-8&useSSL=false username: root password: 123456 hikari: leak-detection-threshold: 2000

定义数据源实体类

我们可以建立个datasourceBean文件夹专门管理数据源的实体类。

我们这里要建立三个实体类。分别对应test1，test2，test3

@Configurationpublic class Test1DataSourceBean { @Value('${spring.datasource.test1.driver-class-name}') private String test1Driver; @Value('${spring.datasource.test1.url}') private String test1Url; @Value('${spring.datasource.test1.username}') private String test1Username; @Value('${spring.datasource.test1.password}') private String test1Password; @Bean(name='test1DataSource') public DataSource test1DataSource() throws Exception{ HikariDataSource dataSource = new HikariDataSource(); dataSource.setDriverClassName(test1Driver); dataSource.setJdbcUrl(test1Url); dataSource.setUsername(test1Username); dataSource.setPassword(test1Password); return dataSource; }}

@Configurationpublic class Test2DataSourceBean { @Value('${spring.datasource.test2.driver-class-name}') private String test2Driver; @Value('${spring.datasource.test2.url}') private String test2Url; @Value('${spring.datasource.test2.username}') private String test2Username; @Value('${spring.datasource.test2.password}') private String test2Password; @Bean(name='test2DataSource') public DataSource test2DataSource() throws Exception{ HikariDataSource dataSource = new HikariDataSource(); dataSource.setDriverClassName(test2Driver); dataSource.setJdbcUrl(test2Url); dataSource.setUsername(test2Username); dataSource.setPassword(test2Password); return dataSource; }}

@Configurationpublic class Test3DataSourceBean { @Value('${spring.datasource.test3.driver-class-name}') private String test3Driver; @Value('${spring.datasource.test3.url}') private String test3Url; @Value('${spring.datasource.test3.username}') private String test3Username; @Value('${spring.datasource.test3.password}') private String test3Password; @Bean(name='test3DataSource') public DataSource test3DataSource() throws Exception{ HikariDataSource dataSource = new HikariDataSource(); dataSource.setDriverClassName(test3Driver); dataSource.setJdbcUrl(test3Url); dataSource.setUsername(test3Username); dataSource.setPassword(test3Password); return dataSource; }}

定义一个枚举类管理数据源

public enum DatabaseType { test1('test1', 'test1'), test2('test2', 'test2'), test3('test3','test3'); private String name; private String value; DatabaseType(String name, String value){ this.name = name; this.value = value; } public String getName(){ return name; } public String getValue(){ return value; }}

定义一个线程安全的数据源容器

public class DatabaseContextHolder { private static final ThreadLocal<DatabaseType> contextHolder = new ThreadLocal<>(); public static void setDatabaseType(DatabaseType type){ contextHolder.set(type); } public static DatabaseType getDatabaseType(){ return contextHolder.get(); }}

定义动态数据源

public class DynamicDataSource extends AbstractRoutingDataSource{ protected Object determineCurrentLookupKey() { return DatabaseContextHolder.getDatabaseType(); }}

mybatis配置类

网上的很多文章配置出来都会产生数据源循环依赖的问题，这里解决了这个问题。

@Configuration@MapperScan(basePackages='cn.test.jichi', sqlSessionFactoryRef='sessionFactory')public class MybatisConfig { /** * @Description:设置动态数据源 */ @Bean(name='dynamicDataSource') @Primary public DynamicDataSource DataSource( @Qualifier('test1DataSource') DataSource test1DataSource, @Qualifier('test2DataSource') DataSource test2DataSource, @Qualifier('test3DataSource') DataSource test3DataSource){ Map<Object, Object> targetDataSource = new HashMap<>(); targetDataSource.put(DatabaseType.test1, test1DataSource); targetDataSource.put(DatabaseType.test2, test2DataSource); targetDataSource.put(DatabaseType.test3, test3DataSource); DynamicDataSource dataSource = new DynamicDataSource(); dataSource.setTargetDataSources(targetDataSource); dataSource.setDefaultTargetDataSource(test1DataSource); return dataSource; } /** * @Description:根据动态数据源创建sessionFactory */ @Bean(name='sessionFactory') public SqlSessionFactory sessionFactory( @Qualifier('test1DataSource') DataSource test1DataSource, @Qualifier('test2DataSource') DataSource test2DataSource, @Qualifier('test3DataSource') DataSource test3DataSource) throws Exception{ SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean(); //构造方法，解决动态数据源循环依赖问题。 sessionFactoryBean.setDataSource(this.DataSource(test1DataSource,test2DataSource, test3DataSource)); return sessionFactoryBean.getObject(); }}

示例

public void testDymnaicDatasource(){ //不切换数据源默认是自己的。 System.out.println('-----默认数据源'); DemoEntity totalCount = demoMapper.getTotalCount(); String nameCount1 = totalCount.getNameCount(); String ageCount2 = totalCount.getAgeCount(); System.out.println('nameCount:'+nameCount1); System.out.println('ageCount:'+ageCount2); //数据源切换为branch System.out.println('-----数据源为test2'); DynamicDataSourceUtils.chooseBranchDataSource(); Integer nameCount = demoMapper.getNameCount(); Integer ageCount = demoMapper.getAgeCount(); System.out.println('nameCount:'+nameCount); System.out.println('ageCount:'+ageCount); //数据源为basic System.out.println('-----数据源为test3'); DynamicDataSourceUtils.chooseBasicDataSource(); Integer ageCount1 = demoMapper.getAgeCount(); System.out.println('ageCount:'+ageCount1); }

总结

至此实现了多数据源的动态切换。可以在同一个方法里面进行操作多个数据源。

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持好吧啦网。