protected void setSystemProperties() {
        ConcurrentHashMap<String, String> systemProperties = configuration.filter("system");
        Iterator it = systemProperties.entrySet().iterator();
        while (it.hasNext()) {
            Map.Entry property = (Map.Entry) it.next();
            String key = (String) property.getKey();
            String val = (String) property.getValue();

            System.setProperty(key, val);

            it.remove(); // avoids a ConcurrentModificationException
        }
    }