Read and write .done files to mark long completion process

done.snippet.java

	public static void writeDoneFile(String filePath) throws IOException {
		String doneFilePath = filePath + ".done";

		FileOutputStream out = null;

		try {
			out = new FileOutputStream(doneFilePath);
			out.write(SimpleDateFormat.getInstance().format(new Date()).getBytes());
		} finally {
			if (out != null) {
				out.close();
			}
		}
	}

	public static Date doneAt(String filePath) throws IOException, ParseException {
		String doneFilePath = filePath + ".done";
		Date date = null;
		FileInputStream in = null;

		try {
			in = new FileInputStream(doneFilePath);
			byte[] buffer = new byte[1024];
			int read = 0;
			if ((read = in.read(buffer)) > 0) {
				String content = new String(buffer, 0, read);
				date = SimpleDateFormat.getInstance().parse(content);
			}
		} finally {
			if (in != null) {
				in.close();
			}
		}

		return date;
	}