如何将JpaRepository用于两个不同的数据源？

@Configuration
@EnableTransactionManagement
public class DataSourceConfig {

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

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

    @Primary
    @Bean(name = "entityManagerFactory")
    public LocalContainerEntityManagerFactoryBean firstEntityManagerFactory(
            EntityManagerFactoryBuilder builder, @Qualifier("firstDataSource") DataSource dataSource) {
        return builder
                .dataSource(dataSource)
                .packages("com.example.first.entity")
                .persistenceUnit("first")
                .build();
    }

    @Bean(name = "secondEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean secondEntityManagerFactory(
            EntityManagerFactoryBuilder builder, @Qualifier("secondDataSource") DataSource dataSource) {
        return builder
                .dataSource(dataSource)
                .packages("com.example.second.entity")
                .persistenceUnit("second")
                .build();
    }

    @Primary
    @Bean(name = "firstRepository")
    public JpaRepository<FirstEntity, Long> firstRepository(
            @Qualifier("entityManagerFactory") EntityManagerFactory entityManagerFactory) {
        return new JpaRepositoryFactory(entityManagerFactory.createEntityManager()).getRepository(FirstRepository.class);
    }

    @Bean(name = "secondRepository")
    public JpaRepository<SecondEntity, Long> secondRepository(
            @Qualifier("secondEntityManagerFactory") EntityManagerFactory entityManagerFactory) {
        return new JpaRepositoryFactory(entityManagerFactory.createEntityManager()).getRepository(SecondRepository.class);
    }
}

@Service
public class MyService {

    @Autowired
    @Qualifier("firstRepository")
    private JpaRepository<FirstEntity, Long> firstRepository;

    @Autowired
    @Qualifier("secondRepository")
    private JpaRepository<SecondEntity, Long> secondRepository;

    // 使用firstRepository和secondRepository进行数据操作
}