Android获取String的MD5值

	/**
	 * 将字符串转成MD5值
	 * 
	 * @param string
	 * @return
	 */
	public static String stringToMD5(String string) {
		byte[] hash;

		try {
			hash = MessageDigest.getInstance("MD5").digest(string.getBytes("UTF-8"));
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			return null;
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
			return null;
		}

		StringBuilder hex = new StringBuilder(hash.length * 2);
		for (byte b : hash) {
			if ((b & 0xFF) < 0x10)
				hex.append("0");
			hex.append(Integer.toHexString(b & 0xFF));
		}

		return hex.toString();
	}