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javajmsqpid

Qpid JMS: Receiving Text Message leads to casting exception

I'm trying to send and receive messages with Qpid JMS and ProtonJ (AMQP 1.0) and cannot receive a TextMessage. The exception says that it cannot cast a JmsBytesMessage to a TextMessage:

org.apache.qpid.jms.message.JmsBytesMessage cannot be cast to javax.jms.TextMessage

Even trying to receive the message as a JmsTextMessage leads to a:

org.apache.qpid.jms.message.JmsBytesMessage cannot be cast to org.apache.qpid.jms.message.JmsTextMessage

I'm sending a message as follows:

  TextMessage textMessage = session.createTextMessage(message)
  Queue queue = session.createQueue(queueName); 
  MessageProducer producer = session.createProducer(queue);
  producer.send(textMessage);

I try to receive the message with:

    Queue queue = session.createQueue(queueName); 
    MessageConsumer consumer = session.createConsumer(queue);
    connection.start();
    TextMessage message = (TextMessage) consumer.receive();

As this did not work I tried to get the Bytes and use the toString method:

 JmsBytesMessage message = (JmsBytesMessage) consumer.receive();  
 String stringMessage = message.toString();

with the following result: 

JmsBytesMessage { org.apache.qpid.jms.provider.amqp.message.AmqpJmsBytesMessageFacade@10664b39 }

With the next test I just used the bytes and turned them into a String:

 JmsBytesMessage message = (JmsBytesMessage) consumer.receive();
 message.readUTF();
 byte[] byteData = null;
 byteData = new byte[(int) message.getBodyLength()];
 message.readBytes(byteData);
 message.reset();
 String messageString = new String(byteData);

The result is Sw�testmessage. I'm wondering what that prefix is as I haven't sent it. I guess it must be some encoding stuff.

How do I receive the message as a String?

Solution

  • QPid JMS will return a TextMessage based variant of the incoming message based on the manner of encoding and annotations that are used to describe the inbound message. If you are receiving a BytesMessage then it implies that the message being delivered it not annotated as being a TextMessage or it is not carrying a content type indicating a string is encoded in the body bytes or it is not a body section that is an AmqpValue type which carries an encoded String.

    Your intermediary may be re-encoding the message incorrectly or you have other messages queued that are not encoded properly.