안정성과 확장성이 뛰어난 분산 시스템을 구축하기 위한 Java 기술 스택

// 服务提供者
@RestController
public class UserController {
    @GetMapping("/users/{id}")
    public User getUser(@PathVariable("id") Integer id) {
        // 从数据库中查询用户数据
        return userService.getUser(id);
    }
}

// 服务消费者
@RestController
public class OrderController {
    @Autowired
    private RestTemplate restTemplate;

    @GetMapping("/orders/{userId}")
    public OrderList getOrders(@PathVariable("userId") Integer userId) {
        // 调用用户服务获取用户信息
        User user = restTemplate.getForObject("http://user-service/users/" + userId, User.class);
        // 从数据库中查询订单数据
        return orderService.getOrders(user.getId());
    }
}

// 服务注册与发现
@SpringBootApplication
@EnableDiscoveryClient
public class UserServiceApplication {
    public static void main(String[] args) {
        SpringApplication.run(UserServiceApplication.class, args);
    }
}

// 配置文件
spring.application.name=user-service
server.port=8081
eureka.client.serviceUrl.defaultZone=http://localhost:8761/eureka/

// 消息生产者
@Service
public class MessageProducer {
    @Autowired
    private KafkaTemplate<String, String> kafkaTemplate;

    public void sendMessage(String topic, String message) {
        kafkaTemplate.send(topic, message);
    }
}

// 消息消费者
@Service
public class MessageConsumer {
    @KafkaListener(topics = "myTopic")
    public void receiveMessage(String message) {
        // 处理收到的消息
        System.out.println("Received message: " + message);
    }
}

// 配置文件
spring.kafka.bootstrap-servers=localhost:9092
spring.kafka.consumer.group-id=myGroup

// 配置Redis连接池
@Bean
public JedisPool jedisPool() {
    JedisPoolConfig poolConfig = new JedisPoolConfig();
    poolConfig.setMaxTotal(100);
    poolConfig.setMaxIdle(20);
    poolConfig.setMinIdle(5);
    JedisPool jedisPool = new JedisPool(poolConfig, "localhost", 6379);
    return jedisPool;
}

// 操作缓存
@Service
public class CacheService {
    @Autowired
    private JedisPool jedisPool;

    public void set(String key, String value) {
        try (Jedis jedis = jedisPool.getResource()) {
            jedis.set(key, value);
        }
    }

    public String get(String key) {
        try (Jedis jedis = jedisPool.getResource()) {
            return jedis.get(key);
        }
    }
}