DirectoryStream<Path> directoryStream;
File in = new File("C:\\Users\\simon\\Desktop\\a"); // 資源文件夾
File out = new File("C:\\Users\\simon\\Desktop\\b"); // 目標文件夾
try {
       directoryStream = Files.newDirectoryStream(in.toPath()); //returning a DirectoryStream to iterate over* all entries in the directory.
       directoryStream.forEach(path -> {
           if (path.getFileName().toString().endsWith(".java")) { // 判斷是否為java文件
               try {
                   Files.copy(path, out.toPath().resolve(path.getFileName().toString().replace(".java", ".txt")), StandardCopyOption.REPLACE_EXISTING); // 重命名為.txt 并且復制到out文件夾
               } catch (IOException e) { // 因為在lambda表達式內，所以要包裹try catch
                   e.printStackTrace();
               }
           }
       });
   } catch (IOException e) {
       e.printStackTrace();
   }

 //對圖片進行重命名
    public String reNameImg(String oldPath, String oneType, String twoType, int count, List<File> files) {
        File source = new File(oldPath);
        String suffixName = source.getName().substring(source.getName().lastIndexOf("."));
        File filePath = new File(rootFileDir + File.separator + "exPort" + File.separator +generatorDataFileName());
        String reName = "";
        try {
            if (!filePath.exists()) {
                filePath.mkdirs();
            }
           File dest =new File(filePath+File.separator+oneType + "-" + twoType + "-" + count + suffixName);
            Files.copy(source.toPath(), dest.toPath(), StandardCopyOption.REPLACE_EXISTING);
            files.add(dest);
            reName = dest.getPath();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return reName;
    }

 //獲取日期目錄
    private String generatorDataFileName() {
        Calendar date = Calendar.getInstance();
        SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHmmss");
        return format.format(date.getTime());
    }