Camel send String to JMS queue but byte array is retrieved

Question

I have a question related to Camel and JMS message.

My system contains a JMS topic and a JMS queue, say, TopicInput and QueueInput. A process of mine listens to QueueInput and process the message send into this queue. The result is then passed to another Topic, say, TopicOutput.

The process that processes the message uses Java and Apache Camel. The response my Camel route send out is a String. Therefore the String is sent to TopicOutput.

My problem is that when I send my message to the QueueInput directly, everything is fine, I get a String response from TopicOutput. However, if I send the request message to the TopicInput, which internally bridges to QueueInput anyway, the result I get from TopicOutput will be a byte array representation of the String.

Does anyone know how this could happen? I am not even sure whether this is the Camel's problem or JMS problem.

Any suggestions or hints will be helpful.

Many thanks.

Maybe post your camel route? And maybe check convertBodyTo here: (camel.apache.org/convertbodyto.html) — Steve Harrington
– Steve Harrington, Commented Apr 29, 2014 at 21:17
How are the JMS destinations TopicInput, QueueInput, and TopicOutput connected? How do you achieve the "interal bridging" of TopicInput and QueueInput? — Peter Keller
– Peter Keller, Commented Apr 30, 2014 at 18:08

Petter Nordlander · Accepted Answer · 2014-04-30 14:20:52Z

2

Not quite sure what's going on exactly in your logic.

JMS has BytesMessage and TextMessage. To get a string directly, the message has to be TextMessage, otherwise a String must be constructed from a byte array, which you can retrieve from the message.

When sending messages using Camel, Camel tries to map the payload to the best JMS message type. Check this table out.

To be sure to always produce a TextMessage (that parses to String), convert the payload to String before sending it with a JMS producer. Make sure you are aware of what the message type and payload is in every step of your flow, then you should easily solve your issue.

answered Apr 30, 2014 at 14:20

Petter Nordlander

22.3k5 gold badges54 silver badges86 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Claus Ibsen Over a year ago

or use the jmsMessageType=Text option in the JMS endpoint where you send the message, then Camel is forced to use a Text message type.

Collectives™ on Stack Overflow

Camel send String to JMS queue but byte array is retrieved

1 Answer 1

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related