default SupportsFileSystemOperations asFileSystemIO() {
    if (supportFileSystemOperations()) {
      return (SupportsFileSystemOperations) this;
    }
    throw new IllegalStateException("Doesn't support directory operations");
  }
Return this cast to {@link SupportsFileSystemOperations} if it is.
amoro-format-iceberg/src/main/java/org/apache/amoro/io/AuthenticatedFileIO.java