dialog = new JFileChooser();
dialog.setCurrentDirectory(new File(lastWorkingPath));
filter = new CommonFileFilter("Gene Category Export (.gce,.txt)");
filter.addExtension("gce");
filter.addExtension("txt");
dialog.setFileFilter(filter);
if( dialog.showOpenDialog(parentComponent) == JFileChooser.APPROVE_OPTION )
{
File file = dialog.getSelectedFile();