标签：hashmap master toc null mysq sql hash [] ctr
前几天有个需求，需要使用不同的数据源，例如某业务要用A数据源，另一个业务要用B数据源。我上网收集了一些资料整合了一下，虽然最后这个需求不了了之了，但是多数据源动态切换还是蛮好用的，所以记录一下，或许以后有用呢？或者自己感兴趣又想玩呢！
1.加个依赖
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.1</version>
</dependency>
2.application.properties配置文件
#主从数据库 master.db.driverClassName=com.mysql.jdbc.Driver master.db.url=jdbc:mysql://localhost:3306/cbd?characterEncoding=UTF-8&useUnicode=true&useSSL=false master.db.username=root master.db.password=admin slave.db.driverClassName=com.mysql.jdbc.Driver slave.db.url=jdbc:mysql://localhost:3306/cbd_test?characterEncoding=UTF-8&useUnicode=true&useSSL=false slave.db.username=root slave.db.password=admin mybatis.config-location= classpath:config/mybatis-config.xml mybatis.mapper-locations=classpath:mapper/**/*.xml
3.禁用springboot默认加载数据源配置
@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class})
public class Application {
public static void main(String[] args) throws Exception {
SpringApplication.run(Application.class, args);
}
}
4.数据源配置类
/** * 主数据源 */ @Configuration @ConfigurationProperties(prefix = "master.db") public class MasterDataSourceConfig { private String url; private String username; private String password; private String driverClassName; }
/** * 从数据源配置 */ @Configuration @ConfigurationProperties(prefix = "slave.db") public class SlaveDataSourceConfig { private String url; private String username; private String password; private String driverClassName; }
/** * 数据源配置类 */ @Configuration public class DataSourceComponent { @Resource private MasterDataSourceConfig masterDataSourceConfig; @Resource private SlaveDataSourceConfig slaveDataSourceConfig; @Bean(name = "master") public DataSource masterDataSource() { DataSource dataSource = new DataSource(); dataSource.setUrl(masterDataSourceConfig.getUrl()); dataSource.setUsername(masterDataSourceConfig.getUsername()); dataSource.setPassword(masterDataSourceConfig.getPassword()); dataSource.setDriverClassName(masterDataSourceConfig.getDriverClassName()); return dataSource; } @Bean(name = "slave") public DataSource slaveDataSource() { DataSource dataSource = new DataSource(); dataSource.setUrl(slaveDataSourceConfig.getUrl()); dataSource.setUsername(slaveDataSourceConfig.getUsername()); dataSource.setPassword(slaveDataSourceConfig.getPassword()); dataSource.setDriverClassName(slaveDataSourceConfig.getDriverClassName()); return dataSource; } @Primary//不加这个会报错。 @Bean(name = "multiDataSource") public MultiRouteDataSource exampleRouteDataSource() { MultiRouteDataSource multiDataSource = new MultiRouteDataSource(); Map<Object, Object> targetDataSources = new HashMap<>(); targetDataSources.put("master", masterDataSource()); targetDataSources.put("slave", slaveDataSource()); multiDataSource.setTargetDataSources(targetDataSources); multiDataSource.setDefaultTargetDataSource(masterDataSource()); return multiDataSource; } }
5.数据源上下文
/** * 数据源上下文 */ public class DataSourceContext { private static final ThreadLocal<String> contextHolder = new ThreadLocal<>(); public static void setDataSource(String value) { contextHolder.set(value); } public static String getDataSource() { return contextHolder.get(); } public static void clearDataSource() { contextHolder.remove(); } }
6.DataSource路由类
/* * 重写的函数决定了最后选择的DataSource */ public class MultiRouteDataSource extends AbstractRoutingDataSource { @Override protected Object determineCurrentLookupKey() { //通过绑定线程的数据源上下文实现多数据源的动态切换,有兴趣的可以去查阅资料或源码 return DataSourceContext.getDataSource(); } }
7.使用，修改上下文中的数据源就可以切换自己想要使用的数据源了。
public UserVO findUser(String username) { DataSourceContext.setDataSource("slave"); UserVO userVO = userMapper.findByVO(username); System.out.println(userVO.getName()+"====================="); return null; }
这种是在业务中使用代码设置数据源的方式，也可以使用AOP+注解的方式实现控制，方法多多！
标签：hashmap master toc null mysq sql hash [] ctr
原文地址：https://www.cnblogs.com/tinyj/p/9864128.html
