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！