void partitionTablesByQuotaTarget(Multimap<TableName, QuotaSettings> quotas,
    Set<TableName> tablesWithTableQuota, Set<TableName> tablesWithNamespaceQuota) {
    // Partition the tables with quotas by table and ns quota
    for (Entry<TableName, QuotaSettings> entry : quotas.entries()) {
      SpaceLimitSettings settings = (SpaceLimitSettings) entry.getValue();
      TableName tn = entry.getKey();
      if (settings.getTableName() != null) {
        tablesWithTableQuota.add(tn);
      }
      if (settings.getNamespace() != null) {
        tablesWithNamespaceQuota.add(tn);
      }

      if (settings.getTableName() == null && settings.getNamespace() == null) {
        fail("Unexpected table name with null tableName and namespace: " + tn);
      }
    }
  }
Waits {@code timeout} milliseconds for the HBase quota table to exist.
hbase-server/src/test/java/org/apache/hadoop/hbase/quotas/SpaceQuotaHelperForTests.java