code: private Set<String> parseInstanceIDs(final Map<String, String[]> queryParams) {
          Set<String> ret = new TreeSet<String>();
  
          Set<Map.Entry<String, String[]>> entries = queryParams.entrySet();
          for (Map.Entry<String, String[]> entry : entries) {
              if (null != entry && null != entry.getKey()
                      && entry.getKey().matches("InstanceId\\.(\\d)+")) {
                  if (null != entry.getValue() && entry.getValue().length > 0) {
                      ret.add(entry.getValue()[0]);
                  }
              }
          }
          return ret;
      }
docs: Parse instance IDs from query parameters.
  
  @param queryParams
  map of query parameters in http request
  @return a set of instance IDs in the parameter map