DataRepository data = getDataRepository();
String prefix = getPrefix();
String dataName = DataRepository.createDataName(prefix, DATA_NAME);
SimpleData d = data.getSimpleValue(dataName);
String subsetPrefix = null;
if (d != null) subsetPrefix = d.format();
if (subsetPrefix == null || subsetPrefix.length() == 0)
subsetPrefix = DEFAULT_PREFIX;
out.print("Location: ");
out.print(TinyWebServer.urlEncodePath(subsetPrefix));