SpringBoot+Dynamic多数据源动态切换

好的，这是一个比较具体的技术问题。首先，Spring Boot可以通过配置多个数据源来实现多数据源的切换。其次，可以使用AOP技术，在方法执行前动态切换数据源。以下是一些关键的代码片段：

1. 在application.properties文件中配置多个数据源

spring.datasource.primary.url=jdbc:mysql://localhost:3306/db1
spring.datasource.primary.username=user1
spring.datasource.primary.password=pass1

spring.datasource.secondary.url=jdbc:mysql://localhost:3306/db2
spring.datasource.secondary.username=user2
spring.datasource.secondary.password=pass2

2. 创建多个数据源的Bean

@Configuration
public class DataSourceConfig {

    @Bean(name = "primaryDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.primary")
    public DataSource primaryDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "secondaryDataSource")
    @ConfigurationProperties(prefix = "spring.datasource.secondary")
    public DataSource secondaryDataSource() {
        return DataSourceBuilder.create().build();
    }

}

3. 创建动态数据源并设置默认数据源

@Configuration
public class DynamicDataSourceConfig {

    @Autowired
    @Qualifier("primaryDataSource")
    private DataSource primaryDataSource;

    @Autowired
    @Qualifier("secondaryDataSource")
    private DataSource secondaryDataSource;

    @Bean(name = "dynamicDataSource")
    public DataSource dynamicDataSource() {
        DynamicDataSource dynamicDataSource = new DynamicDataSource();
        Map<Object, Object> targetDataSources = new HashMap<>();
        targetDataSources.put(DataSourceType.PRIMARY.name(), primaryDataSource);
        targetDataSources.put(DataSourceType.SECONDARY.name(), secondaryDataSource);
        dynamicDataSource.setTargetDataSources(targetDataSources);
        dynamicDataSource.setDefaultTargetDataSource(primaryDataSource);
        return dynamicDataSource;
    }

    @Bean
    public JdbcTemplate jdbcTemplate() {
        return new JdbcTemplate(dynamicDataSource());
    }

}

4. 创建AOP切面，在方法执行前根据注解切换数据源

@Aspect
@Component
public class DataSourceAspect {

    @Autowired
    @Qualifier("dynamicDataSource")
    private DataSource dynamicDataSource;

    @Pointcut("@annotation(com.example.demo.datasource.DataSource)")
    public void dataSourcePointCut() {}

    @Before("dataSourcePointCut()")
    public void before(JoinPoint joinPoint) {
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        DataSource dataSource = signature.getMethod().getAnnotation(DataSource.class);
        if (dataSource != null) {
            DataSourceType dataSourceType = dataSource.value();
            DynamicDataSourceContextHolder.setDataSourceType(dataSourceType.name());
        }
    }

    @After("dataSourcePointCut()")
    public void after(JoinPoint joinPoint) {
        DynamicDataSourceContextHolder.clearDataSourceType();
    }

}

5. 在需要切换数据源的方法上添加注解

@DataSource(DataSourceType.SECONDARY)
public List<User> listUsers() {
    return jdbcTemplate.query("SELECT * FROM user", new BeanPropertyRowMapper<>(User.class));
}

这样就可以实现动态切换多数据源了。希望能够帮到你！