docs: protected void process(MatchCallback callback) {
          Yaml yaml = new Yaml();
          boolean found = false;
          for (Resource resource : resources) {
              try {
                  int count = 0;
                  for (Object object : yaml.loadAll(resource.getInputStream())) {
                      if (resolutionMethod != ResolutionMethod.FIRST_FOUND || !found) {
                          @SuppressWarnings("unchecked")
                          Map<String, Object> map = (Map<String, Object>) object;
                          if (map != null) {
                              process(map, callback);
                              found = true;
                              count++;
                          }
                      }
                  }
  
                  logger.debug("Loaded " + count + " document" + (count > 1 ? "s" : "") + " from YAML resource: "
                      + resource);
  
                  if (resolutionMethod == ResolutionMethod.FIRST_FOUND && found) {
                      // No need to load any more resources
                      break;
                  }
              } catch (IOException e) {
                  if (e instanceof FileNotFoundException && e.getMessage().contains("${APPLICATION_CONFIG_FILE}") &&
                      (resolutionMethod == ResolutionMethod.FIRST_FOUND
                          || resolutionMethod == ResolutionMethod.OVERRIDE_AND_IGNORE)) {
                      logger.debug("Could not load map from " + resource + ": " + e.getMessage());
                  } else if (resolutionMethod == ResolutionMethod.FIRST_FOUND
                                  || resolutionMethod == ResolutionMethod.OVERRIDE_AND_IGNORE) {
                      logger.warn("Could not load map from " + resource + ": " + e.getMessage());
                  }
                  else {
                      throw new IllegalStateException(e);
                  }
              }
          }
      }