Spring Boot 具有使用相同存储库和模型类的多个数据源

使用Spring Boot框架的应用程序通常需要与一个或多个数据源交互，这可能是不同的数据库或其他外部服务。在某些情况下，我们可能希望在应用程序中使用相同的存储库和模型类来访问这些不同的数据源。本文将介绍如何在Spring Boot中实现这一目标，并提供一个案例代码来说明该过程。

properties
# 第一个数据源
spring.datasource.url=jdbc:mysql://localhost:3306/db1
spring.datasource.username=user1
spring.datasource.password=pass1
# 第二个数据源
datasource2.url=jdbc:mysql://localhost:3306/db2
datasource2.username=user2
datasource2.password=pass2

java
@Configuration
public class DataSourceConfig {
    
    @Value("${spring.datasource.url}")
    private String datasource1Url;
    @Value("${spring.datasource.username}")
    private String datasource1Username;
    @Value("${spring.datasource.password}")
    private String datasource1Password;
    @Value("${datasource2.url}")
    private String datasource2Url;
    @Value("${datasource2.username}")
    private String datasource2Username;
    @Value("${datasource2.password}")
    private String datasource2Password;
    @Bean
    @Primary
    public DataSource dataSource1() {
        return DataSourceBuilder.create()
                .url(datasource1Url)
                .username(datasource1Username)
                .password(datasource1Password)
                .build();
    }
    @Bean(name = "dataSource2")
    public DataSource dataSource2() {
        return DataSourceBuilder.create()
                .url(datasource2Url)
                .username(datasource2Username)
                .password(datasource2Password)
                .build();
    }
}

java
@Configuration
@EnableJpaRepositories(
        basePackages = "com.example.repository",
        entityManagerFactoryRef = "entityManagerFactory1"
)
public class JpaConfig {
    @Autowired
    @Qualifier("dataSource1")
    private DataSource dataSource1;
    @Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory1(EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(dataSource1)
                .packages("com.example.model")
                .build();
    }
}

java
@Repository
public interface UserRepository extends JpaRepository {
    // 定义自定义的查询方法
    List findByFirstName(String firstName);
}

java
@SpringBootApplication
public class MultiDataSourceExampleApplication {
    public static void main(String[] args) {
        SpringApplication.run(MultiDataSourceExampleApplication.class, args);
    }
}
@Entity
@Table(name = "users")
class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    @Column(name = "first_name")
    private String firstName;
    @Column(name = "last_name")
    private String lastName;
    // getters and setters
}
@Repository
public interface UserRepository extends JpaRepository {
    // 定义自定义的查询方法
    List findByFirstName(String firstName);
}
@RestController
@RequestMapping("/users")
public class UserController {
    @Autowired
    private UserRepository userRepository;
    @GetMapping
    public List getAllUsers() {
        return userRepository.findAll();
    }
    @GetMapping("/{firstName}")
    public List getUsersByFirstName(@PathVariable String firstName) {
        return userRepository.findByFirstName(firstName);
    }
}