code: private static String _constructRowKey(String namespace, String scope, String metric, String tagKey, String tagValue, String tableName) {
          namespace = namespace == null ? Character.toString(PLACEHOLDER_FOR_NULL_STRINGS) : namespace;
          tagKey = tagKey == null ? Character.toString(PLACEHOLDER_FOR_NULL_STRINGS) : tagKey;
          tagValue = tagValue == null ? Character.toString(PLACEHOLDER_FOR_NULL_STRINGS) : tagValue;
  
          String key;
  
          if (SCOPE_SCHEMA_TABLENAME.equals(tableName)) {
              key = MessageFormat.format("{0}{5}{1}{5}{2}{5}{3}{5}{4}", scope, metric, tagKey, tagValue, namespace, ROWKEY_SEPARATOR);
          } else if (METRIC_SCHEMA_TABLENAME.equals(tableName)) {
              key = MessageFormat.format("{0}{5}{1}{5}{2}{5}{3}{5}{4}", metric, scope, tagKey, tagValue, namespace, ROWKEY_SEPARATOR);
          } else {
              throw new SystemException(new IllegalArgumentException("Unknown table: " + tableName));
          }
          return key;
      }
docs: ~ Methods **************************************************************************************************************************************