Java 到指定目錄查找檔案

import java.io.File;

public class DirSize {
    public static void main(String[] args) {
        File dir = new File("/home/huanyu/Desktop");
        String[] files = dir.list();
        if (files == null){
            System.out.println("目錄為空！！！");
        }else {
            for (int i=0; i<files.length; i++){
                System.out.println(files[i]);
            }
        }
    }
}