if (f == currentFilter) setFileFilter(null);
  public boolean removeChoosableFileFilter(FileFilter f)  {    FileFilter[] old = getChoosableFileFilters();    if (! choosableFilters.remove(f))      return false;    FileFilter[] newFilters = getChoosableFileFilters();    firePropertyChange(CHOOSABLE_FILE_FILTER_CHANGED_PROPERTY, old, newFilters);    return true;  }