public void writeLog() {
		FileOutputStream fos = null;
		File logPath = new File("D:/Excel", "log.txt");
		try {
			fos = new FileOutputStream(logPath);
			fos.write(log.toString().getBytes());
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				if (fos != null)
					fos.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}