ch.setFileFilter(new TiledFileFilter());
ch.setFileFilter(new TiledFileFilter(TiledFileFilter.FILTER_TMX));
    private void openMap() {        String startLocation = "";        if (currentMap != null) {            startLocation = currentMap.getFilename();        }        JFileChooser ch = new JFileChooser(startLocation);		ch.setFileFilter(new TiledFileFilter());        int ret = ch.showOpenDialog(appFrame);        if (ret == JFileChooser.APPROVE_OPTION) {            loadMap(ch.getSelectedFile().getAbsolutePath());        }    }