Java Stream - 如何排序目录和文件

import java.io.File;
import java.nio.file.Paths;
import java.util.Arrays;
import java.util.stream.Stream;


public class Main {

  public static void main(String[] args) {
    final String dir = "E:\\Java_Dev\\";
    final File file = Paths.get(dir).toFile();
    File[] files = file.listFiles();
    Arrays.sort(files, (f1, f2) -> {
      if(f1.isDirectory() != f2.isDirectory()) {
        if(f1.isDirectory()) {
          return -1;
        } else {
          return 1;
        }
      }
      else {
        return f1.getName().toLowerCase().compareTo(f2.getName().toLowerCase());
      }
    });
    Stream.of(files)
        .forEach(System.out::println);
  }
}