/**
		     * 字母转换数字
		     * @param phoneNumber
		     * @return
		     */
		    public static String normalizeNumber(String phoneNumber) {
		        StringBuilder sb = new StringBuilder();
		        int len = phoneNumber.length();
		        for (int i = 0; i < len; i++) {
		            char c = phoneNumber.charAt(i);
		            // Character.digit() supports ASCII and Unicode digits (fullwidth, Arabic-Indic, etc.)
		            int digit = Character.digit(c, 10);
		            if (digit != -1) {
		                sb.append(digit);
		            } else if (i == 0 && c == '+') {
		                sb.append(c);
		            } else if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
		                return normalizeNumber(PhoneNumberUtils.convertKeypadLettersToDigits(phoneNumber));
		            }
		        }
		        return sb.toString();
		    }