java 获取上传文件的MD5值

/**
	 * 获取上传文件的md5
	 * 
	 * @param file
	 * @return
	 * @throws NoSuchAlgorithmException
	 * @throws IOException
	 */
	public String getMd5(MultipartFile file) {

		try {
			byte[] uploadBytes = file.getBytes();
			MessageDigest md5 = MessageDigest.getInstance("MD5");
			byte[] digest = md5.digest(uploadBytes);
			String hashString = new BigInteger(1, digest).toString(16);
			return hashString;
		} catch (Exception e) {
			LogUtil.writeErrorLog(e.toString(), e);
		}
		return null;

	}