public void saveConfiguration() {
        PrintWriter pw = null;
        try {
            pw = new PrintWriter(new FileWriter("./config/configuration.txt"));
        } catch (IOException ex) {
            System.err.println("Unable to update settings!");
            System.err.println(ex.getMessage());
            return;
        }
        
        // Write each key=value pair.
        for (String key : configuration.keySet()) {
            pw.println(key + "=" + configuration.get(key));
        }
        
        pw.close();
    }