java - 如何在 Spring Controller 中注入(inject) Cache-Control max-age header ？

Question

我在 Spring Controller 中有以下方法:

public Response myMethod (@PathVariable("id") String id,
        @RequestParam(required = false) Map<String, Object> queryString,
        @RequestHeader(value = HttpHeaders.ACCEPT, required = false) String acceptHeader,
        @RequestHeader(value = HttpHeaders.CACHE_CONTROL, required = false, defaultValue = 1) String expiration,
        @RequestHeader(value = HttpHeaders.FROM) String appId) {
// ...
}

在这里，我使用 @RequestHeader 提取整个缓存控制 header 。有没有办法仅通过注入(inject)或使用专用 Spring 类进一步解析来获取 max-age 部分？还是我必须手动完成？

谢谢

Answer 1

您也许可以定义一个类，例如:CacheControlMaxAge ，然后是 Converter<HttpRequest, CacheControlMaxAge> ，最后将您的参数声明为一个CacheControlMaxAge

@Getter
@RequiredArgsConstructor
public class CacheControlMaxAge {
  private final int maxAge;
}

@Component
public class CacheControlMaxAgeConverter implements Converter<HttpRequest, CacheControlMaxAge> {

  public CacheControlMaxAge convert(HttpRequest request) {
    // todo: extract stuff from request
    return new CacheControlMaxAge(...);
  }
}

public Response blah(..., CacheControlMaxAge cacheControl) { ... }