public Set<DatabaseTableName> getCachedTableNames() {
        // use partition cache to get all cached table names because partition cache is more accurate,
        // table cache will be cached when user use `use catalog.db` command.
        return partitionCache.asMap().keySet().stream().map(hivePartitionName ->
                DatabaseTableName.of(hivePartitionName.getDatabaseName(), hivePartitionName.getTableName())).collect(
                Collectors.toSet());
    }
@Test
    public void testGetCachedName() {
        CachingHiveMetastore cachingHiveMetastore = new CachingHiveMetastore(
                metastore, executor, expireAfterWriteSec, refreshAfterWriteSec, 1000, false);
        HiveCacheUpdateProcessor processor = new HiveCacheUpdateProcessor(
                "hive_catalog", cachingHiveMetastore, null, null, false, false);
        Assert.assertTrue(processor.getCachedTableNames().isEmpty());

        processor = new HiveCacheUpdateProcessor("hive_catalog", metastore, null, null, false, false);
        Assert.assertTrue(processor.getCachedTableNames().isEmpty());
    }