Java method to list all files inside a directory, and print out with indentation.

List.java

	public static void walkDirectory(File file) {
		int levels = file.getAbsolutePath().length() - file.getAbsolutePath().replace(File.separator, "").length();
		try {
			Files.walk(file.toPath()).map(Path::toFile).forEach((File f) -> {
				int subLevels = f.getAbsolutePath().length() - f.getAbsolutePath().replace(File.separator, "").length()
						- levels;
				String indent = new String(new char[(subLevels) * 4]).replace('\0', ' ');
				System.out.println(indent + f.getName() + (f.isDirectory() ? ":" : ""));
			});
		} catch (IOException e) {
			e.printStackTrace();
		}
	}