java如何扫描文件夹呢？

实现思路:
    使用Files.walkFileTree方法即可完成指定文件夹的扫描

public static void main(String[] args) {
    Collection<File> all = new Arraylist<File>();
    addTree(new File("."), all);
    System.out.println(all);
}

static void addTree(Path directory, final Collection<Path> all)
        throws IOException {
    Files.walkFileTree(directory, new SimpleFileVisitor<Path>() {
        @Override
        public FileVisitResult visitFile(Path file, BasicFileAttributes attrs)
                throws IOException {
            all.add(file);
            return FileVisitResult.CONTINUE;
        }
    });
}