名称: springboot-patterns 描述: Spring Boot 架构模式、REST API 设计、分层服务、数据访问、缓存、异步处理和日志记录。适用于 Java Spring Boot 后端开发工作。
Spring Boot 开发模式
适用于可扩展、生产级服务的 Spring Boot 架构与 API 模式。
REST API 结构
@RestController
@RequestMapping("/api/markets")
@Validated
class MarketController {
private final MarketService marketService;
MarketController(MarketService marketService) {
this.marketService = marketService;
}
@GetMapping
ResponseEntity<Page<MarketResponse>> list(
@RequestParam(defaultValue = "0") int page,
@RequestParam(defaultValue = "20") int size) {
Page<Market> markets = marketService.list(PageRequest.of(page, size));
return ResponseEntity.ok(markets.map(MarketResponse::from));
}
@PostMapping
ResponseEntity<MarketResponse> create(@Valid @RequestBody CreateMarketRequest request) {
Market market = marketService.create(request);
return ResponseEntity.status(HttpStatus.CREATED).body(MarketResponse.from(market));
}
}
仓储模式 (Repository Pattern - Spring Data JPA)
public interface MarketRepository extends JpaRepository<MarketEntity, Long> {
@Query("select m from MarketEntity m where m.status = :status order by m.volume desc")
List<MarketEntity> findActive(@Param("status") MarketStatus status, Pageable pageable);
}
带事务的服务层 (Service Layer with Transactions)
@Service
public class MarketService {
private final MarketRepository repo;
public MarketService(MarketRepository repo) {
this.repo = repo;
}
@Transactional
public Market create(CreateMarketRequest request) {
MarketEntity entity = MarketEntity.from(request);
MarketEntity saved = repo.save(entity);
return Market.from(saved);
}
}
DTO 与校验 (DTOs and Validation)
public record CreateMarketRequest(
@NotBlank @Size(max = 200) String name,
@NotBlank @Size(max = 2000) String description,
@NotNull @FutureOrPresent Instant endDate,
@NotEmpty List<@NotBlank String> categories) {}
public record MarketResponse(Long id, String name, MarketStatus status) {
static MarketResponse from(Market market) {
return new MarketResponse(market.id(), market.name(), market.status());
}
}
异常处理 (Exception Handling)
@ControllerAdvice
class GlobalExceptionHandler {
@ExceptionHandler(MethodArgumentNotValidException.class)
ResponseEntity<ApiError> handleValidation(MethodArgumentNotValidException ex) {
String message = ex.getBindingResult().getFieldErrors().stream()
.map(e -> e.getField() + ": " + e.getDefaultMessage())
.collect(Collectors.joining(", "));
return ResponseEntity.badRequest().body(ApiError.validation(message));
}
@ExceptionHandler(AccessDeniedException.class)
ResponseEntity<ApiError> handleAccessDenied() {
return ResponseEntity.status(HttpStatus.FORBIDDEN).body(ApiError.of("Forbidden"));
}
@ExceptionHandler(Exception.class)
ResponseEntity<ApiError> handleGeneric(Exception ex) {
// 记录带有堆栈跟踪的非预期错误
return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
.body(ApiError.of("Internal server error"));
}
}
缓存 (Caching)
需要在配置类上添加 @EnableCaching。
@Service
public class MarketCacheService {
private final MarketRepository repo;
public MarketCacheService(MarketRepository repo) {
this.repo = repo;
}
@Cacheable(value = "market", key = "#id")
public Market getById(Long id) {
return repo.findById(id)
.map(Market::from)
.orElseThrow(() -> new EntityNotFoundException("Market not found"));
}
@CacheEvict(value = "market", key = "#id")
public void evict(Long id) {}
}
异步处理 (Async Processing)
需要在配置类上添加 @EnableAsync。
@Service
public class NotificationService {
@Async
public CompletableFuture<Void> sendAsync(Notification notification) {
// 发送 邮件/短信
return CompletableFuture.completedFuture(null);
}
}
日志记录 (Logging - SLF4J)
@Service
public class ReportService {
private static final Logger log = LoggerFactory.getLogger(ReportService.class);
public Report generate(Long marketId) {
log.info("generate_report marketId={}", marketId);
try {
// 业务逻辑
} catch (Exception ex) {
log.error("generate_report_failed marketId={}", marketId, ex);
throw ex;
}
return new Report();
}
}
中间件 / 过滤器 (Middleware / Filters)
@Component
public class RequestLoggingFilter extends OncePerRequestFilter {
private static final Logger log = LoggerFactory.getLogger(RequestLoggingFilter.class);
@Override
protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response,
FilterChain filterChain) throws ServletException, IOException {
long start = System.currentTimeMillis();
try {
filterChain.doFilter(request, response);
} finally {
long duration = System.currentTimeMillis() - start;
log.info("req method={} uri={} status={} durationMs={}",
request.getMethod(), request.getRequestURI(), response.getStatus(), duration);
}
}
}
分页与排序 (Pagination and Sorting)
PageRequest page = PageRequest.of(pageNumber, pageSize, Sort.by("createdAt").descending());
Page<Market> results = marketService.list(page);
容错性外部调用 (Error-Resilient External Calls)
public <T> T withRetry(Supplier<T> supplier, int maxRetries) {
int attempts = 0;
while (true) {
try {
return supplier.get();
} catch (Exception ex) {
attempts++;
if (attempts >= maxRetries) {
throw ex;
}
try {
Thread.sleep((long) Math.pow(2, attempts) * 100L);
} catch (InterruptedException ie) {
Thread.currentThread().interrupt();
throw ex;
}
}
}
}
限流 (Filter + Bucket4j)
安全注意事项：X-Forwarded-For 请求头默认是不可信的，因为客户端可以伪造它。
仅在以下情况下使用转发请求头：
- 你的应用位于受信任的反向代理（nginx、AWS ALB 等）之后
- 你已将
ForwardedHeaderFilter注册为 Bean - 你在 application 属性中配置了
server.forward-headers-strategy=NATIVE或FRAMEWORK - 你的代理配置为覆盖（而非追加）
X-Forwarded-For请求头
当 ForwardedHeaderFilter 配置正确时，request.getRemoteAddr() 将自动从转发头中返回正确的客户端 IP。如果没有此配置，请直接使用 request.getRemoteAddr()——它返回直接连接的 IP，这是唯一可信的值。
@Component
public class RateLimitFilter extends OncePerRequestFilter {
private final Map<String, Bucket> buckets = new ConcurrentHashMap<>();
/*
* 安全提示：此过滤器使用 request.getRemoteAddr() 来识别用于限流的客户端。
*
* 如果你的应用位于反向代理（nginx、AWS ALB 等）之后，你必须配置 Spring
* 正确处理转发头，以便准确检测客户端 IP：
*
* 1. 在 application.properties/yaml 中设置 server.forward-headers-strategy=NATIVE
* (适用于云平台) 或 FRAMEWORK
* 2. 如果使用 FRAMEWORK 策略，请注册 ForwardedHeaderFilter：
*
* @Bean
* ForwardedHeaderFilter forwardedHeaderFilter() {
* return new ForwardedHeaderFilter();
* }
*
* 3. 确保你的代理覆盖（而不是追加）X-Forwarded-For 请求头以防止伪造
* 4. 为你的容器配置 server.tomcat.remoteip.trusted-proxies 或等效配置
*
* 如果没有这些配置，request.getRemoteAddr() 将返回代理服务器的 IP，而非客户端 IP。
* 不要直接读取 X-Forwarded-For —— 在没有受信任代理处理的情况下，它是极易伪造的。
*/
@Override
protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response,
FilterChain filterChain) throws ServletException, IOException {
// 使用 getRemoteAddr()，它在配置了 ForwardedHeaderFilter 时返回正确的客户端 IP，
// 否则返回直接连接的 IP。在没有正确代理配置的情况下，切勿直接信任 X-Forwarded-For 头。
String clientIp = request.getRemoteAddr();
Bucket bucket = buckets.computeIfAbsent(clientIp,
k -> Bucket.builder()
.addLimit(Bandwidth.classic(100, Refill.greedy(100, Duration.ofMinutes(1))))
.build());
if (bucket.tryConsume(1)) {
filterChain.doFilter(request, response);
} else {
response.setStatus(HttpStatus.TOO_MANY_REQUESTS.value());
}
}
}
后台任务 (Background Jobs)
使用 Spring 的 @Scheduled 或集成队列（如 Kafka、SQS、RabbitMQ）。保持处理程序具有幂等性和可观测性。
可观测性 (Observability)
- 通过 Logback encoder 实现结构化日志（JSON）
- 指标（Metrics）：Micrometer + Prometheus/OTel
- 链路追踪（Tracing）：使用 OpenTelemetry 或 Brave 后端的 Micrometer Tracing
生产环境默认实践 (Production Defaults)
- 优先使用构造函数注入，避免字段注入
- 为 RFC 7807 错误启用
spring.mvc.problemdetails.enabled=true(Spring Boot 3+) - 根据工作负载配置 HikariCP 连接池大小并设置超时
- 为查询使用
@Transactional(readOnly = true) - 通过
@NonNull和Optional在适当时强制执行空安全（null-safety）
切记：保持控制器（Controller）薄、服务（Service）专注、仓储（Repository）简单，并集中处理错误。针对可维护性和可测试性进行优化。