if (url == null) { }
    public static String lookup(String username)    throws BackendException {        log.finer("lookup(String)");                // Initialize the hash map, if we haven't already.        synchronized (initialized) {            if (initialized.booleanValue()) {                // Create hashtable of domain names to LDAP URLs.                String domain, url;                for (int i=1; ; i++) {                    try {                        domain = Configuration.getProperty("no.feide.moria.backend.ldap"+i+".domain");                        if (domain == null)                            break;  // No more mappings.                        url = Configuration.getProperty("no.feide.moria.backend.ldap"+i+".url");                    } catch (ConfigurationException e) {                        log.severe("ConfigurationException caught and re-thrown as BackendException");                        throw new BackendException("ConfigurationException caught and re-thrown as BackendException");                    }                    if (url == null)                        break;  // More of a sanity check; possible syntax error in config file.                    urlMap.put(domain, url);                    log.config(domain+" mapped to "+url);                }            }        }                // Map user ID domain to LDAP URL using the username suffix.        String domain = username;        if (domain.indexOf('@') == -1) {            log.severe("Illegal user identifier; missing @: "+domain);            throw new BackendException("Illegal user identifier; missing @: "+domain);        }         domain = domain.substring(domain.indexOf('@')+1);        String url = (String)urlMap.get(domain);        log.info("Matched domain "+domain+" to LDAP URL "+url);                return url;            }