listFiles() in Java fails to get all files

Question

I wrote this function and it seemed okey but it fails if there are more than one folders in the current directory and no files. It enters only the first folder and does it job there and ignores the other folders. How can I fix this bug?

public static void getAllFiles(File folder, List<File> result) {
    File[] listOfFiles = folder.listFiles();
    for (int i = 0; i < listOfFiles.length; i++) {
        if (listOfFiles[i].isFile()) {
           result.add(listOfFiles[i]);
        }
        if (listOfFiles[i].isDirectory()) {
            getAllFiles(listOfFiles[i], result);
        }
    }
}

Answer 1

Maybe you should try walkFileTree method from NIO.2:

public List<Path> findAllFilesInDirectory(Path pathToDir) throws IOException {
    final List<Path> pathsToFiles = new ArrayList<>();

    Files.walkFileTree(pathToDir, new SimpleFileVisitor<Path>() {
        @Override
        public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
            if (Files.isRegularFile(file)) {
                pathsToFiles.add(file);
            }
            return FileVisitResult.CONTINUE;
        }
    });

    return pathsToFiles;
}

To using NIO.2 You have to have at least a Java 1.7 version.

Documentation:

http://docs.oracle.com/javase/tutorial/essential/io/walk.html

Tutorials:

http://www.javabeat.net/visiting-all-the-files-and-directories-for-a-directory-in-java-using-nio2/

http://www.srccodes.com/p/article/20/java-file-and-directory-operations-made-easy-in-jdk7

Answer 2

I tried it as:

public void listf(String directoryName, List<File> files){ File directory = new File(directoryName) // get all the files from a directory File[] fList = directory.listFiles(); for (File file : fList) { if (file.isFile()) { files.add(file); } else if (file.isDirectory()) { listf(file.getAbsolutePath(), files); } } }