title: Why won't topic messages get dequeued?
body: <p>I want to ask a question about the topics of activemq.</p>
  
  <p>I entered admin page of activemq and found that messages enqueued will never be dequeued in topics even if consumers had been written correctly.  That means the all published messages will be permanently kept in ActiveMQ.</p>
  
  <p>Will these message lead to a memory leak?  Is there a solution that could make consumed messages dequeued?</p>
  
  <p><img src="https://i.stack.imgur.com/WdP4C.jpg" alt="enter image description here"></p>