Get handshake response headers

For example get session id from headers

mStompClient.lifecycle().subscribe(lifecycleEvent -> {
            switch (lifecycleEvent.getType()) {
                case OPENED:
                    mSessionCookie = parseSessionId(lifecycleEvent.getHandshakeResponseHeaders());
                    break;
                case ERROR:
                   // ...
                    break;
                case CLOSED:
                    LOGD(TAG, "Stomp connection closed");
            }
        });

private String parseSessionId(TreeMap<String, String> headers) {
        if (headers == null) return null;
        String cookies = headers.get("Set-Cookie");
        if (cookies == null) return null;
        Matcher matcher = COOKIE_SESSION_PATTERN.matcher(cookies);
        if (matcher.find()) {
            return matcher.group();
        } else return null;
}