private static void expectAddressesAreNonEmpty(Field field, Tensor tensor) {
        if (tensor.isEmpty()) {
            throw new IllegalArgumentException("Remove update for field '" + field.getName() +
                                               "' does not contain tensor addresses");
        }
    }
Reader of a "remove" update of a tensor field.
document/src/main/java/com/yahoo/document/json/readers/TensorRemoveUpdateReader.java