Getting the filenames of all files in a folder

想要實作一個瀏覽file system 的功能, 需要列出某一個路徑下的檔案或目錄清單, 畫面:

解法:
https://stackoverflow.com/questions/5694385/getting-the-filenames-of-all-files-in-a-folder

File folder = new File("your/path");
File[] listOfFiles = folder.listFiles();

for (int i = 0; i < listOfFiles.length; i++) {
  if (listOfFiles[i].isFile()) {
    System.out.println("File " + listOfFiles[i].getName());
  } else if (listOfFiles[i].isDirectory()) {
    System.out.println("Directory " + listOfFiles[i].getName());
  }
}

解法2:
https://stackabuse.com/java-list-files-in-a-directory/

public class ListFilesRecursively {
    public void listFiles(String startDir) {
        File dir = new File(startDir);
        File[] files = dir.listFiles();

        if (files != null && files.length > 0) {
            for (File file : files) {
                // Check if the file is a directory
                if (file.isDirectory()) {
                    // We will not print the directory name, just use it as a new
                    // starting point to list files from
                    listDirectory(file.getAbsolutePath());
                } else {
                    // We can use .length() to get the file size
                    System.out.println(file.getName() + " (size in bytes: " + file.length()+")");
                }
            }
        }
    }
    public static void main(String[] args) {
        ListFilesRecursively test = new ListFilesRecursively();
        String startDir = ("D:/Programming");
        test.listFiles(startDir);
    }
}

output:

yout-file-name.txt (size in bytes: 12345)