Check 手机号码

private void checkPhoneNum(String phone, String code) {        if (code.startsWith("+")) {            code = code.substring(1);        }        if (TextUtils.isEmpty(phone)) {            Toast.makeText(getApplicationContext(), "请输入手机号码",Toast.LENGTH_SHORT).show();            return;        }        if (code == "86") {            if (phone.length() != 11) {                Toast.makeText(getApplicationContext(), "手机号码长度不对",Toast.LENGTH_SHORT).show();                return;            }        }        String rule = "^1(3|5|7|8|4)\\d{9}";        Pattern p = Pattern.compile(rule);        Matcher m = p.matcher(phone);        if (!m.matches()) {            Toast.makeText(getApplicationContext(), "您输入的手机号码格式不正确",Toast.LENGTH_SHORT).show();            return;        }    }