I have the same issue as described here: ActiveMQ: One Pending Message but Queue is empty.
Active MQ shows pending messages for the queue but when I click it it's empty.
We persist our messages not in default kaha db but in Oracle DB. I could see the pending messages in database in table ACTIVEMQ_MSGS.
After restart of activeMQ all clients worked as expected. In the administration console I could see the messages and the java consumer consumed the messages.
The mentioned exsiting issue was solved with an update to ActiveMQ 5.7.0. I checked the activeMQ logs but I didn't found errors or warnings. Producer for the messages was also not changed.
Any idea why I experience these issues?
Issue is solved now. I also asked in the active mq mailing list: http://activemq.2283324.n4.nabble.com/One-Pending-Message-but-Queue-is-empty-ActiveMQ-5-12-0-td4715720.html.
First of all we added this method call in our client:
org.apache.camel.ConsumerTemplate.doneUoW(Exchange exchange)
but it didn't solve the problem finally