code: public static <T> T unmarshal(InputStream is, Map<String, String> parameters) throws KubernetesClientException {
      String specFile = readSpecFileFromInputStream(is);
      if (containsMultipleDocuments(specFile)) {
        return (T) getKubernetesResourceList(parameters, specFile);
      }
      return unmarshal(new ByteArrayInputStream(specFile.getBytes()), JSON_MAPPER, parameters);
    }
docs: Unmarshals a stream optionally performing placeholder substitution to the stream.
  @param is    The {@link InputStream}.
  @param parameters  A {@link Map} with parameters for placeholder substitution.
  @param <T>   The target type.
  @return returns returns de-serialized object
  @throws KubernetesClientException KubernetesClientException