case RECEIPT:
String receiptHeader = frame.headers().get(StompHeaders.RECEIPT_ID);
if (state == ClientState.AUTHENTICATED && receiptHeader.equals(subscrReceiptId)) {
StompFrame msgFrame = new DefaultStompFrame(StompCommand.SEND);
msgFrame.headers().set(StompHeaders.DESTINATION, StompClient.TOPIC);
msgFrame.content().writeBytes("some payload".getBytes());
System.out.println("subscribed, sending message frame: " + msgFrame);
state = ClientState.SUBSCRIBED;
ctx.writeAndFlush(msgFrame);
} else if (state == ClientState.DISCONNECTING && receiptHeader.equals(disconReceiptId)) {
System.out.println("disconnected");