list all files in the folder and also sub folders [duplicate]

Answer 1

You can return a List instead of an array and things gets much simpler.

    public static List listf(String directoryName) {
        File directory = new File(directoryName);

        List resultList = new ArrayList();

        // get all the files from a directory
        File[] fList = directory.listFiles();
        resultList.addAll(Arrays.asList(fList));
        for (File file : fList) {
            if (file.isFile()) {
                System.out.println(file.getAbsolutePath());
            } else if (file.isDirectory()) {
                resultList.addAll(listf(file.getAbsolutePath()));
            }
        }
        //System.out.println(fList);
        return resultList;
    }