code: private String[] getMappedServers(final ServerInformationCatalog serverInformationCatalog,
              final Map<String, String> mappedServers) {
  
          if (serverInformationCatalog.containsServer(HadoopResource.DEFAULT_CLUSTERREFERENCE)) {
              mappedServers.put("(default)", HadoopResource.DEFAULT_CLUSTERREFERENCE);
          }
  
          final String[] serverNames = serverInformationCatalog.getServerNames();
          for (int i = 0; i < serverNames.length; i++) {
              final String serverName = serverNames[i];
              if (!serverName.equals(HadoopResource.DEFAULT_CLUSTERREFERENCE)) {
                  mappedServers.put(serverName, serverName);
              }
          }
          return mappedServers.keySet().toArray(new String[serverNames.length]);
      }
docs: We avoid having HadoopResource.DEFAULT_CLUSTERREFERENCE(
  "org.datacleaner.hadoop.environment") as a server name. We write
  "default" instead.