JButton browseButton = new JButton("Browse");
browseButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
JFileChooser fileChooser = new JFileChooser();
int chooseResult = fileChooser.showDialog(filenameField, "Select");
if (chooseResult == JFileChooser.APPROVE_OPTION) {
if (fileChooser.getSelectedFile().isFile()) {
setFile(fileChooser.getSelectedFile());
}
}