doc/java-broker/src/docbkx/runtime/Java-Broker-Runtime-Close-On-No-Route.xml

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<section xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="Java-Broker-Runtime-Close-Connection-When-No-Route">
  <title>Closing client connections on unroutable mandatory messages</title>

  <section xml:id="Java-Broker-Runtime-Close-Connection-When-No-Route-Summary">
  <title>Summary</title>
    <para>
        Due to asynchronous nature of AMQP 0-8/0-9/0-9-1 protocols sending a message with a routing key for which no queue binding exist results
        in either message being bounced back (if it is mandatory or immediate) or discarded on broker side otherwise.
    </para>
    <para>
        When a 'mandatory' message is returned, the Apache Qpid JMS AMQP 0-x clients conveys this by delivering
        an <emphasis>AMQNoRouteException</emphasis> through the configured ExceptionListener on the Connection.
        This does not cause channel or connection closure, however it requires a special exception handling
        on client side in order to deal with <emphasis>AMQNoRouteExceptions</emphasis>.
        This could potentially be a problem when using various messaging frameworks (e.g. Mule)
        as they usually close the connection on receiving any JMSException.
    </para>
    <para>
        In order to simplify application handling of scenarios where 'mandatory' messages
        are being sent to queues which do not actually exist, the Apache Qpid Broker-J can be configured such that
        it will respond to this situation by closing the connection
        rather than returning the unroutable message to the client as it normally should.
        From the application perspective, this will result in failure of synchronous operations in progress such as a session commit() call.
    </para>
    <note>
        <para>This feature affects only transacted sessions.</para>
        <para>
           By default, the Apache Qpid JMS AMQP 0-x produces mandatory messages when using queue destinations.  Topic
           destinations produce 'non-mandatory' messages.
        </para>
    </note>
  </section>
  <section xml:id="Java-Broker-Runtime-Close-Connection-When-No-Route-Configuration">
    <title>Configuring
        <emphasis>closeWhenNoRoute</emphasis>
    </title>
    <para>
        The Port attribute <emphasis>closeWhenNoRoute</emphasis> can be set to specify this feature on broker side.
        By default, it is turned on. Setting <emphasis>closeWhenNoRoute</emphasis> to <emphasis>false</emphasis> switches
        it off.
    </para>
      <para>See the <link xmlns:xlink="http://www.w3.org/1999/xlink"
                          xlink:href="${qpidJmsClient08Book}JMS-Client-0-8-Connection-URL.html">Qpid JMS AMQP 0-x client
          documentation</link> for details of enabling this feature client side.
      </para>
  </section>
</section>