| <div class="docbook"><div class="navheader"><table summary="Navigation header" width="100%"><tr><th align="center" colspan="3">7.7. Queues</th></tr><tr><td align="left" width="20%"><a accesskey="p" href="Java-Broker-Management-Managing-Exchanges.html">Prev</a> </td><th align="center" width="60%">Chapter 7. Managing Entities</th><td align="right" width="20%"> <a accesskey="n" href="Java-Broker-Management-Managing-Consumers.html">Next</a></td></tr></table><hr /></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a id="Java-Broker-Management-Managing-Queues"></a>7.7. Queues</h2></div></div></div><p><a class="link" href="Java-Broker-Concepts-Queues.html" title="4.7. Queues">Queues</a> are named entities that | |
| hold/buffer messages for later delivery to consumer applications.</p><p>Queues can be managed using the HTTP or AMQP channels.</p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Management-Managing-Queues-Types"></a>7.7.1. Types</h3></div></div></div><p>The Broker supports four different queue types, each with different delivery semantics.</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p><a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-Standard" title="4.7.1.1. Standard">Standard</a> - a simple First-In-First-Out (FIFO) queue</p></li><li class="listitem"><p><a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-Priority" title="4.7.1.2. Priority">Priority</a> - delivery order depends on the priority of each message</p></li><li class="listitem"><p><a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-Sorted" title="4.7.1.3. Sorted Queues">Sorted</a> - | |
| delivery order depends on the value of the sorting key property in each message</p></li><li class="listitem"><p><a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-LVQ" title="4.7.1.4. Last Value Queues (LVQ)">Last Value | |
| Queue</a> - also known as an LVQ, retains only the last (newest) message received | |
| with a given LVQ key value</p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Management-Managing-Queues-Attributes"></a>7.7.2. Attributes</h3></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p><span class="emphasis"><em>Name of the queue</em></span>. Message consumers and browsers refer to this | |
| name when they wish to subscribe to queue to receive messages from it.</p></li><li class="listitem"><p><span class="emphasis"><em>Type of the queue</em></span>. Can be either <a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-Standard" title="4.7.1.1. Standard">standard</a>, <a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-Priority" title="4.7.1.2. Priority">priority</a>, <a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-Sorted" title="4.7.1.3. Sorted Queues">sorted</a>, or <a class="link" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Types-LVQ" title="4.7.1.4. Last Value Queues (LVQ)">lvq</a>.</p></li><li class="listitem"><p><span class="emphasis"><em>Durable</em></span>. Whether the queue survives a restart. Messages on a | |
| non durable queue do not survive a restart even if they are marked persistent.</p></li><li class="listitem"><p><span class="emphasis"><em>Maximum/Minimum TTL</em></span>. Defines a maximum and minimum time-to-live (TTL). Messages | |
| arriving with TTL larger than the maximum (including those with no TTL at all, which are considered to | |
| have a TTL of infinity) will be overridden by the maximum. Similarly, messages arriving with TTL less | |
| than the minimum, will be overridden by the minimum. | |
| </p><p>Changing these values affects only new arrivals, existing messages already on the | |
| queue are not affected.</p></li><li class="listitem"><p><span class="emphasis"><em>Message persistent override</em></span>. Allow message persistent settings | |
| of incoming messages to be overridden. Changing this value affects only new arrivals, | |
| existing messages on the queue are not affected. </p></li><li class="listitem"><p><span class="emphasis"><em>Overflow policy</em></span>. Queues have the ability to limit the of the | |
| cumulative size of all the messages contained within the store. This feature is | |
| described in detail <a class="xref" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queue-OverflowPolicy" title="4.7.5. Controlling Queue Size">Section 4.7.5, “Controlling Queue Size”</a>.</p></li><li class="listitem"><p><span class="emphasis"><em>Alerting Thresholds</em></span>. Queues have the ability to alert on a | |
| variety of conditions: total queue depth exceeded a number or size, message age exceeded | |
| a threshold, message size exceeded a threshold. These thresholds are soft. See <a class="xref" href="Java-Broker-Appendix-Queue-Alerts.html" title="Appendix E. Queue Alerts">Appendix E, <em>Queue Alerts</em></a></p></li><li class="listitem"><p><span class="emphasis"><em>Message Groups</em></span>. See <a class="xref" href="Java-Broker-Concepts-Queues.html#Java-Broker-Concepts-Queues-Message-Grouping" title="4.7.2. Messaging Grouping">Section 4.7.2, “Messaging Grouping”</a></p></li><li class="listitem"><p><span class="emphasis"><em>maximumDeliveryAttempts</em></span>. See <a class="xref" href="Java-Broker-Runtime-Handling-Undeliverable-Messages.html" title="9.4. Handing Undeliverable Messages">Section 9.4, “Handing Undeliverable Messages”</a></p></li><li class="listitem"><p><span class="emphasis"><em>alternateBinding</em></span>. Provides an alternate destination that will be used when the | |
| number of delivery attempts exceeds the <span class="emphasis"><em>maximumDeliveryAttempts</em></span> configured on this | |
| queue. Messages are also routed to this destination if this queue is deleted.</p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="Java-Broker-Management-Managing-Queue-Lifecycle"></a>7.7.3. Lifecycle</h3></div></div></div><p>Not supported</p></div></div><div class="navfooter"><hr /><table summary="Navigation footer" width="100%"><tr><td align="left" width="40%"><a accesskey="p" href="Java-Broker-Management-Managing-Exchanges.html">Prev</a> </td><td align="center" width="20%"><a accesskey="u" href="Java-Broker-Management-Managing-Entities.html">Up</a></td><td align="right" width="40%"> <a accesskey="n" href="Java-Broker-Management-Managing-Consumers.html">Next</a></td></tr><tr><td align="left" valign="top" width="40%">7.6. Exchanges </td><td align="center" width="20%"><a accesskey="h" href="Apache-Qpid-Broker-J-Book.html">Home</a></td><td align="right" valign="top" width="40%"> 7.8. Consumers</td></tr></table></div></div> |