private String defaultUri(Namespace namespace) throws TException {
    return HIVE_METASTORE_EXTENSION.metastoreClient().getConfigValue(
        "hive.metastore.warehouse.external.dir", "") +  "/" + namespace.level(0) + ".db";
  }
Run all the tests from abstract of {@link CatalogTests} with few specific tests related to HIVE.
iceberg/iceberg-catalog/src/test/java/org/apache/iceberg/hive/TestHiveCatalog.java