doc/book/src/java-broker/Java-Broker-Concepts-Queues.xml

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<section id="Java-Broker-Concepts-Queues">
<title>Queues</title>
<para><emphasis>Queue</emphasis>s are named entities within a <emphasis>Virtual Host</emphasis> that hold/buffer messages for delivery to consumer applications.</para>
<para>Different types of <emphasis>Queue</emphasis> have different delivery semantics. The following Queues types are currently supported:
    <itemizedlist>
        <listitem><para><link linkend="Java-Broker-Queues">Standard</link>: a simple First-In-First-Out (FIFO) queue</para></listitem>
        <listitem><para><link linkend="Java-Broker-Queues-OtherTypes-Priority">Priority</link>: delivery order depends on the priority of each message</para></listitem>
        <listitem><para><link linkend="Java-Broker-Queues-OtherTypes-Sorted">Sorted</link>: delivery order depends on the value of the sorting key property in each message</para></listitem>
        <listitem><para><link linkend="Java-Broker-Queues-OtherTypes-LVQ">Last Value Queue</link>: also known as an LVQ, retains only the last (newest) message received with a given LVQ key value.</para></listitem>
     </itemizedlist>
</para>
<para>Queue configuration details are covered in <xref linkend="Java-Broker-Queues"/>.</para>
</section>