用File类中的 mkdir 实现 mkdirs（代码）

public static void main(String[] args) {
        String[] directories = {"a","b","c","d","e"};
        File root = new File("d:/");
        for (int i = 0; i < directories.length; i++) 
        {
            File directory = new File(root, directories[i]);
            directory.mkdir();
            root = directory;
        }
    }