Listing files from a folder

Question

Hello I am using Jfilechooser to pick up files on the system.

Only now I need to use Jfilechooser to select folders and add all their contents in the program. I used DIRECTORIES_ONLY and it worked. Now I want to add all the files (through a file type filto (mp3)) in an arrayList and show to the user. But I’ve already searched a lot of the internet and the codes I find as a base do not serve/do not work. Could someone help me?

I need to use Jfilechooser, not . walk

Currently, I’m trying to do it this way:

adicionarPasta.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            final JFileChooser chooser = new JFileChooser();
            chooser.showOpenDialog(parent);
            chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY); 
            String diretorio = chooser.getAbsolutePath();//essa linha está com erro
            // TODO Auto-generated method stub
            File file = new File(diretorio);
            File afile[] = file.listFiles();
            int i = 0;
            for (int j = afile.length; i < j; i++) {
                File arquivos = afile[i];
                System.out.println(arquivos.getName());
            }
        }
    });

Answer 1

Using Java 8

If you want to return the objects File:

private ArrayList<File> listar(String caminho, String extensao) {
  File pasta = new File(caminho);

  return this.listar(pasta, extensao);
}

private ArrayList<File> listar(File pasta, String extensao) {
  ArrayList<File> arquivos;

  arquivos = new ArrayList<>(Arrays.asList(pasta.listFiles()));
  arquivos.removeIf(arquivo -> !arquivo.getName().endsWith(extensao));

  return arquivos;
}

The use would be as follows:

final JFileChooser chooser = new JFileChooser();
chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
chooser.showOpenDialog(null);

System.out.println(this.listar(chooser.getSelectedFile(), ".mp3"));

Answer 2

The method getSelectedFiles of javax.swing.Jfilechooser returns a File[]. You can use it to return an array of File Objects, after enabling multiple selection with setMultiSelectionEnabled. If you do not enable multiple selection, you cannot select multiple files at once, and return them all with getSelectecdFiles.