private JFileChooser setFilters(JFileChooser jfc, boolean predefined, String comment, String extension) {
        if (predefined || 
                !jfc.getFileFilter().getDescription().equalsIgnoreCase("Todos los Archivos")) {
            jfc.setAcceptAllFileFilterUsed(false);
        }
        FileNameExtensionFilter newFilter = new FileNameExtensionFilter(comment, extension);
        jfc.addChoosableFileFilter(newFilter);
        if (predefined) {jfc.setFileFilter(newFilter);}
        return jfc;
    }