Spring cloud stream Message Type Conversion Issue

General Discussions
1

Hi Team,

We get the type casting issue when spring cloud stream reply the message to non spring cloud stream service.

com.solacesystems.jcsmp.impl.BytesMessageImpl cannot be cast to com.solacesystems.jcsmp.TextMessage"

Code:

Below is the code used in the non spring cloud stream service which is type casting to text message which sent by spring cloud stream service.

textMessage.setText(((TextMessage)replyMessage).getText());

Do we need to type cast to BytesMessage and use getData API and convert to String?

2

HI @as63010 …! Yeah, that’s exactly right. The Spring Cloud Stream binder supports all of the standard formats of a Solace message (bytes, text, map, stream), and so your receiving app should do some checks:

if (message instanceof TextMessage) {
  String payload = ((TextMessage)message).getText();
  // work with that
} else if (message instanceof BytesMessage) {
  byte[] payload = ((BytesMessage)messsage).getData();
  // work with bytes.
  // if you know it's a UTF-8 string, you can do something else like:
  //   String payload = new String(((BytesMessage)messsage).getData(),Charset.forName("UTF-8"));
} else ...

And a tip, because lots of people hit this problem: don’t use getBytes() as that is a legacy leftover method for retrieving the XML Content portion of the message, which is disused. BytesMessage is getData(). Weird, I know.