//TODO ... ugly, isn't it?
static public synchronized void initialize(File workingDir) throws JSONException, IOException{
if(singleton==null){
InputStream prefixesIn = GRefineServiceManager.class.getResourceAsStream("/files/prefixes");
PrefixManager prefixManager = new PrefixManager(prefixesIn);
singleton = new GRefineServiceManager(new ServiceRegistry(new GRefineJsonUtilitiesImpl(),prefixManager), workingDir);
File servicesFile= new File(workingDir,"services");
if(servicesFile.exists()){
FileInputStream in = new FileInputStream(servicesFile);
singleton.registry.loadFromFile(in);
}