http://git-wip-us.apache.org/repos/asf/activemq-6/blob/8ecd255f/docs/user-manual/en/management.xml ---------------------------------------------------------------------- diff --git a/docs/user-manual/en/management.xml b/docs/user-manual/en/management.xml new file mode 100644 index 0000000..be5cd32 --- /dev/null +++ b/docs/user-manual/en/management.xml @@ -0,0 +1,1109 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- ============================================================================= --> +<!-- Copyright © 2009 Red Hat, Inc. and others. --> +<!-- --> +<!-- The text of and illustrations in this document are licensed by Red Hat under --> +<!-- a Creative Commons AttributionâShare Alike 3.0 Unported license ("CC-BY-SA"). --> +<!-- --> +<!-- An explanation of CC-BY-SA is available at --> +<!-- --> +<!-- http://creativecommons.org/licenses/by-sa/3.0/. --> +<!-- --> +<!-- In accordance with CC-BY-SA, if you distribute this document or an adaptation --> +<!-- of it, you must provide the URL for the original version. --> +<!-- --> +<!-- Red Hat, as the licensor of this document, waives the right to enforce, --> +<!-- and agrees not to assert, Section 4d of CC-BY-SA to the fullest extent --> +<!-- permitted by applicable law. --> +<!-- ============================================================================= --> + +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"; [ +<!ENTITY % BOOK_ENTITIES SYSTEM "HornetQ_User_Manual.ent"> +%BOOK_ENTITIES; +]> +<chapter id="management"> + <title>Management</title> + <para>HornetQ has an extensive management API that allows a user to modify a server + configuration, create new resources (e.g. JMS queues and topics), inspect these resources + (e.g. how many messages are currently held in a queue) and interact with it (e.g. to remove + messages from a queue). All the operations allows a client to <emphasis>manage</emphasis> + HornetQ. It also allows clients to subscribe to management notifications.</para> + <para>There are 3 ways to manage HornetQ:</para> + <itemizedlist> + <listitem> + <para>Using JMX -- JMX is the standard way to manage Java applications</para> + </listitem> + <listitem> + <para>Using the core API -- management operations are sent to HornetQ server using + <emphasis>core messages</emphasis></para> + </listitem> + <listitem> + <para>Using the JMS API -- management operations are sent to HornetQ server using + <emphasis>JMS messages</emphasis></para> + </listitem> + </itemizedlist> + <para>Although there are 3 different ways to manage HornetQ each API supports the same + functionality. If it is possible to manage a resource using JMX it is also possible to achieve + the same result using Core messages or JMS messages.</para> + <para>This choice depends on your requirements, your application settings and your environment to + decide which way suits you best.</para> + <section> + <title>The Management API</title> + <para>Regardless of the way you <emphasis>invoke</emphasis> management operations, the + management API is the same.</para> + <para>For each <emphasis>managed resource</emphasis>, there exists a Java interface describing + what can be invoked for this type of resource.</para> + <para>HornetQ exposes its managed resources in 2 packages:</para> + <itemizedlist> + <listitem> + <para><emphasis>Core</emphasis> resources are located in the <literal + >org.hornetq.api.core.management</literal> package</para> + </listitem> + <listitem> + <para><emphasis>JMS</emphasis> resources are located in the <literal + >org.hornetq.api.jms.management</literal> package</para> + </listitem> + </itemizedlist> + <para>The way to invoke a <emphasis>management operations</emphasis> depends whether JMX, core + messages, or JMS messages are used.</para> + <note> + <para>A few management operations requires a <literal>filter</literal> parameter to chose + which messages are involved by the operation. Passing <literal>null</literal> or an + empty string means that the management operation will be performed on <emphasis>all + messages</emphasis>.</para> + </note> + <section> + <title>Core Management API</title> + <para>HornetQ defines a core management API to manage core resources. For full details of + the API please consult the javadoc. In summary:</para> + <section id="management.core.server"> + <title>Core Server Management</title> + <itemizedlist> + <listitem> + <para>Listing, creating, deploying and destroying queues</para> + <para>A list of deployed core queues can be retrieved using the <literal + >getQueueNames()</literal> method.</para> + <para>Core queues can be created or destroyed using the management operations + <literal>createQueue()</literal> or <literal>deployQueue()</literal> or + <literal>destroyQueue()</literal>)on the <literal + >HornetQServerControl</literal> (with the ObjectName <literal + >org.hornetq:module=Core,type=Server</literal> or the resource name <literal + >core.server</literal>)</para> + <para><literal>createQueue</literal> will fail if the queue already exists while + <literal>deployQueue</literal> will do nothing.</para> + </listitem> + <listitem> + <para>Pausing and resuming Queues</para> + <para>The <literal>QueueControl</literal> can pause and resume the underlying + queue. When a queue is paused, it will receive messages but will not deliver + them. When it's resumed, it'll begin delivering the queued messages, if any. + </para> + </listitem> + <listitem> + <para>Listing and closing remote connections</para> + <para>Client's remote addresses can be retrieved using <literal + >listRemoteAddresses()</literal>. It is also possible to close the + connections associated with a remote address using the <literal + >closeConnectionsForAddress()</literal> method.</para> + <para>Alternatively, connection IDs can be listed using <literal + >listConnectionIDs()</literal> and all the sessions for a given connection + ID can be listed using <literal>listSessions()</literal>.</para> + </listitem> + <listitem> + <para>Transaction heuristic operations</para> + <para>In case of a server crash, when the server restarts, it it possible that + some transaction requires manual intervention. The <literal + >listPreparedTransactions()</literal> method lists the transactions which + are in the prepared states (the transactions are represented as opaque Base64 + Strings.) To commit or rollback a given prepared transaction, the <literal + >commitPreparedTransaction()</literal> or <literal + >rollbackPreparedTransaction()</literal> method can be used to resolve + heuristic transactions. Heuristically completed transactions can be listed + using the <literal>listHeuristicCommittedTransactions()</literal> and <literal + >listHeuristicRolledBackTransactions</literal> methods.</para> + </listitem> + <listitem> + <para>Enabling and resetting Message counters</para> + <para>Message counters can be enabled or disabled using the <literal + >enableMessageCounters()</literal> or <literal + >disableMessageCounters()</literal> method. To reset message counters, it is + possible to invoke <literal>resetAllMessageCounters()</literal> and <literal + >resetAllMessageCounterHistories()</literal> methods.</para> + </listitem> + <listitem> + <para>Retrieving the server configuration and attributes</para> + <para>The <literal>HornetQServerControl</literal> exposes HornetQ server + configuration through all its attributes (e.g. <literal>getVersion()</literal> + method to retrieve the server's version, etc.)</para> + </listitem> + <listitem> + <para>Listing, creating and destroying Core bridges and diverts</para> + <para>A list of deployed core bridges (resp. diverts) can be retrieved using the <literal + >getBridgeNames()</literal> (resp. <literal>getDivertNames()</literal>) method.</para> + <para>Core bridges (resp. diverts) can be created or destroyed using the management operations + <literal>createBridge()</literal> and <literal>destroyBridge()</literal> + (resp. <literal>createDivert()</literal> and <literal>destroyDivert()</literal>) on the <literal + >HornetQServerControl</literal> (with the ObjectName <literal + >org.hornetq:module=Core,type=Server</literal> or the resource name <literal + >core.server</literal>).</para> + </listitem> + <listitem> + <para>It is possible to stop the server and force failover to occur with any currently attached clients.</para> + <para>to do this use the <literal>forceFailover()</literal> on the <literal + >HornetQServerControl</literal> (with the ObjectName <literal + >org.hornetq:module=Core,type=Server</literal> or the resource name <literal + >core.server</literal>) </para> + <para> + <note>Since this method actually stops the server you will probably receive some sort of error + depending on which management service you use to call it.</note> + </para> + </listitem> + </itemizedlist> + </section> + <section> + <title>Core Address Management</title> + <para>Core addresses can be managed using the <literal>AddressControl</literal> class + (with the ObjectName <literal>org.hornetq:module=Core,type=Address,name="<the + address name>"</literal> or the resource name <literal>core.address.<the + address name></literal>). </para> + <itemizedlist> + <listitem> + <para>Modifying roles and permissions for an address</para> + <para>You can add or remove roles associated to a queue using the <literal + >addRole()</literal> or <literal>removeRole()</literal> methods. You can + list all the roles associated to the queue with the <literal + >getRoles()</literal> method</para> + </listitem> + </itemizedlist> + </section> + <section> + <title>Core Queue Management</title> + <para>The bulk of the core management API deals with core queues. The <literal + >QueueControl</literal> class defines the Core queue management operations (with + the ObjectName <literal>org.hornetq:module=Core,type=Queue,address="<the bound + address>",name="<the queue name>"</literal> or the resource name <literal + >core.queue.<the queue name></literal>).</para> + <para>Most of the management operations on queues take either a single message ID (e.g. + to remove a single message) or a filter (e.g. to expire all messages with a given + property.)</para> + <itemizedlist> + <listitem> + <para>Expiring, sending to a dead letter address and moving messages</para> + <para>Messages can be expired from a queue by using the <literal + >expireMessages()</literal> method. If an expiry address is defined, + messages will be sent to it, otherwise they are discarded. The queue's + expiry address can be set with the <literal>setExpiryAddress()</literal> + method.</para> + <para>Messages can also be sent to a dead letter address with the <literal + >sendMessagesToDeadLetterAddress()</literal> method. It returns the number + of messages which are sent to the dead letter address. If a dead letter address + is not defined, message are removed from the queue and discarded. The queue's + dead letter address can be set with the <literal + >setDeadLetterAddress()</literal> method.</para> + <para>Messages can also be moved from a queue to another queue by using the + <literal>moveMessages()</literal> method.</para> + </listitem> + <listitem> + <para>Listing and removing messages</para> + <para>Messages can be listed from a queue by using the <literal + >listMessages()</literal> method which returns an array of <literal + >Map</literal>, one <literal>Map</literal> for each message.</para> + <para>Messages can also be removed from the queue by using the <literal + >removeMessages()</literal> method which returns a <literal + >boolean</literal> for the single message ID variant or the number of + removed messages for the filter variant. The <literal + >removeMessages()</literal> method takes a <literal>filter</literal> + argument to remove only filtered messages. Setting the filter to an empty + string will in effect remove all messages.</para> + </listitem> + <listitem> + <para>Counting messages</para> + <para>The number of messages in a queue is returned by the <literal + >getMessageCount()</literal> method. Alternatively, the <literal + >countMessages()</literal> will return the number of messages in the queue + which <emphasis>match a given filter</emphasis></para> + </listitem> + <listitem> + <para>Changing message priority</para> + <para>The message priority can be changed by using the <literal + >changeMessagesPriority()</literal> method which returns a <literal + >boolean</literal> for the single message ID variant or the number of + updated messages for the filter variant.</para> + </listitem> + <listitem> + <para>Message counters</para> + <para>Message counters can be listed for a queue with the <literal + >listMessageCounter()</literal> and <literal + >listMessageCounterHistory()</literal> methods (see <xref + linkend="management.message-counters"/>). The message counters can also be + reset for a single queue using the <literal>resetMessageCounter()</literal> + method.</para> + </listitem> + <listitem> + <para>Retrieving the queue attributes</para> + <para>The <literal>QueueControl</literal> exposes Core queue settings through its + attributes (e.g. <literal>getFilter()</literal> to retrieve the queue's filter + if it was created with one, <literal>isDurable()</literal> to know whether the + queue is durable or not, etc.)</para> + </listitem> + <listitem> + <para>Pausing and resuming Queues</para> + <para>The <literal>QueueControl</literal> can pause and resume the underlying + queue. When a queue is paused, it will receive messages but will not deliver + them. When it's resume, it'll begin delivering the queued messages, if any. + </para> + </listitem> + </itemizedlist> + </section> + <section> + <title>Other Core Resources Management</title> + <para>HornetQ allows to start and stop its remote resources (acceptors, diverts, + bridges, etc.) so that a server can be taken off line for a given period of time + without stopping it completely (e.g. if other management operations must be performed + such as resolving heuristic transactions). These resources are:</para> + <itemizedlist> + <listitem> + <para>Acceptors</para> + <para>They can be started or stopped using the <literal>start()</literal> or. + <literal>stop()</literal> method on the <literal>AcceptorControl</literal> + class (with the ObjectName <literal + >org.hornetq:module=Core,type=Acceptor,name="<the acceptor + name>"</literal> or the resource name <literal>core.acceptor.<the + address name></literal>). The acceptors parameters can be retrieved using + the <literal>AcceptorControl</literal> attributes (see <xref + linkend="configuring-transports.acceptors"/>)</para> + </listitem> + <listitem> + <para>Diverts</para> + <para>They can be started or stopped using the <literal>start()</literal> or + <literal>stop()</literal> method on the <literal>DivertControl</literal> + class (with the ObjectName <literal + >org.hornetq:module=Core,type=Divert,name=<the divert name></literal> + or the resource name <literal>core.divert.<the divert name></literal>). + Diverts parameters can be retrieved using the <literal>DivertControl</literal> + attributes (see <xref linkend="diverts"/>)</para> + </listitem> + <listitem> + <para>Bridges</para> + <para>They can be started or stopped using the <literal>start()</literal> (resp. + <literal>stop()</literal>) method on the <literal>BridgeControl</literal> + class (with the ObjectName <literal + >org.hornetq:module=Core,type=Bridge,name="<the bridge + name>"</literal> or the resource name <literal>core.bridge.<the bridge + name></literal>). Bridges parameters can be retrieved using the <literal + >BridgeControl</literal> attributes (see <xref linkend="core-bridges" + />)</para> + </listitem> + <listitem> + <para>Broadcast groups</para> + <para>They can be started or stopped using the <literal>start()</literal> or + <literal>stop()</literal> method on the <literal + >BroadcastGroupControl</literal> class (with the ObjectName <literal + >org.hornetq:module=Core,type=BroadcastGroup,name="<the broadcast group + name>"</literal> or the resource name <literal + >core.broadcastgroup.<the broadcast group name></literal>). Broadcast + groups parameters can be retrieved using the <literal + >BroadcastGroupControl</literal> attributes (see <xref + linkend="clusters"/>)</para> + </listitem> + <listitem> + <para>Discovery groups</para> + <para>They can be started or stopped using the <literal>start()</literal> or + <literal>stop()</literal> method on the <literal + >DiscoveryGroupControl</literal> class (with the ObjectName <literal + >org.hornetq:module=Core,type=DiscoveryGroup,name="<the discovery group + name>"</literal> or the resource name <literal>core.discovery.<the + discovery group name></literal>). Discovery groups parameters can be + retrieved using the <literal>DiscoveryGroupControl</literal> attributes (see + <xref linkend="clusters"/>)</para> + </listitem> + <listitem> + <para>Cluster connections</para> + <para>They can be started or stopped using the <literal>start()</literal> or + <literal>stop()</literal> method on the <literal + >ClusterConnectionControl</literal> class (with the ObjectName <literal + >org.hornetq:module=Core,type=ClusterConnection,name="<the cluster + connection name>"</literal> or the resource name <literal + >core.clusterconnection.<the cluster connection name></literal>). + Cluster connections parameters can be retrieved using the <literal + >ClusterConnectionControl</literal> attributes (see <xref + linkend="clusters"/>)</para> + </listitem> + </itemizedlist> + </section> + </section> + <section> + <title>JMS Management API</title> + <para>HornetQ defines a JMS Management API to manage JMS <emphasis>administrated + objects</emphasis> (i.e. JMS queues, topics and connection factories).</para> + <section> + <title>JMS Server Management</title> + <para>JMS Resources (connection factories and destinations) can be created using the + <literal>JMSServerControl</literal> class (with the ObjectName <literal + >org.hornetq:module=JMS,type=Server</literal> or the resource name <literal + >jms.server</literal>).</para> + <itemizedlist> + <listitem> + <para>Listing, creating, destroying connection factories</para> + <para>Names of the deployed connection factories can be retrieved by the <literal + >getConnectionFactoryNames()</literal> method.</para> + <para>JMS connection factories can be created or destroyed using the <literal + >createConnectionFactory()</literal> methods or <literal + >destroyConnectionFactory()</literal> methods. These connection factories + are bound to JNDI so that JMS clients can look them up. If a graphical console + is used to create the connection factories, the transport parameters are + specified in the text field input as a comma-separated list of key=value (e.g. + <literal>key1=10, key2="value", key3=false</literal>). If there are multiple + transports defined, you need to enclose the key/value pairs between curly + braces. For example <literal>{key=10}, {key=20}</literal>. In that case, the + first <literal>key</literal> will be associated to the first transport + configuration and the second <literal>key</literal> will be associated to the + second transport configuration (see <xref linkend="configuring-transports"/> + for a list of the transport parameters)</para> + </listitem> + <listitem> + <para>Listing, creating, destroying queues</para> + <para>Names of the deployed JMS queues can be retrieved by the <literal + >getQueueNames()</literal> method.</para> + <para>JMS queues can be created or destroyed using the <literal + >createQueue()</literal> methods or <literal>destroyQueue()</literal> + methods. These queues are bound to JNDI so that JMS clients can look them + up</para> + </listitem> + <listitem> + <para>Listing, creating/destroying topics</para> + <para>Names of the deployed topics can be retrieved by the <literal + >getTopicNames()</literal> method.</para> + <para>JMS topics can be created or destroyed using the <literal + >createTopic()</literal> or <literal>destroyTopic()</literal> methods. These + topics are bound to JNDI so that JMS clients can look them up</para> + </listitem> + <listitem> + <para>Listing and closing remote connections</para> + <para>JMS Clients remote addresses can be retrieved using <literal + >listRemoteAddresses()</literal>. It is also possible to close the + connections associated with a remote address using the <literal + >closeConnectionsForAddress()</literal> method.</para> + <para>Alternatively, connection IDs can be listed using <literal + >listConnectionIDs()</literal> and all the sessions for a given connection + ID can be listed using <literal>listSessions()</literal>.</para> + </listitem> + </itemizedlist> + </section> + <section> + <title>JMS ConnectionFactory Management</title> + <para>JMS Connection Factories can be managed using the <literal + >ConnectionFactoryControl</literal> class (with the ObjectName <literal + >org.hornetq:module=JMS,type=ConnectionFactory,name="<the connection factory + name>"</literal> or the resource name <literal>jms.connectionfactory.<the + connection factory name></literal>).</para> + <itemizedlist> + <listitem> + <para>Retrieving connection factory attributes</para> + <para>The <literal>ConnectionFactoryControl</literal> exposes JMS + ConnectionFactory configuration through its attributes (e.g. <literal + >getConsumerWindowSize()</literal> to retrieve the consumer window size for + flow control, <literal>isBlockOnNonDurableSend()</literal> to know whether the + producers created from the connection factory will block or not when sending + non-durable messages, etc.)</para> + </listitem> + </itemizedlist> + </section> + <section> + <title>JMS Queue Management</title> + <para>JMS queues can be managed using the <literal>JMSQueueControl</literal> class (with + the ObjectName <literal>org.hornetq:module=JMS,type=Queue,name="<the queue + name>"</literal> or the resource name <literal>jms.queue.<the queue + name></literal>). </para> + <para><emphasis>The management operations on a JMS queue are very similar to the + operations on a core queue. </emphasis></para> + <itemizedlist> + <listitem> + <para>Expiring, sending to a dead letter address and moving messages</para> + <para>Messages can be expired from a queue by using the <literal + >expireMessages()</literal> method. If an expiry address is defined, + messages will be sent to it, otherwise they are discarded. The queue's + expiry address can be set with the <literal>setExpiryAddress()</literal> + method.</para> + <para>Messages can also be sent to a dead letter address with the <literal + >sendMessagesToDeadLetterAddress()</literal> method. It returns the number + of messages which are sent to the dead letter address. If a dead letter address + is not defined, message are removed from the queue and discarded. The queue's + dead letter address can be set with the <literal + >setDeadLetterAddress()</literal> method.</para> + <para>Messages can also be moved from a queue to another queue by using the + <literal>moveMessages()</literal> method.</para> + </listitem> + <listitem> + <para>Listing and removing messages</para> + <para>Messages can be listed from a queue by using the <literal + >listMessages()</literal> method which returns an array of <literal + >Map</literal>, one <literal>Map</literal> for each message.</para> + <para>Messages can also be removed from the queue by using the <literal + >removeMessages()</literal> method which returns a <literal + >boolean</literal> for the single message ID variant or the number of + removed messages for the filter variant. The <literal + >removeMessages()</literal> method takes a <literal>filter</literal> + argument to remove only filtered messages. Setting the filter to an empty + string will in effect remove all messages.</para> + </listitem> + <listitem> + <para>Counting messages</para> + <para>The number of messages in a queue is returned by the <literal + >getMessageCount()</literal> method. Alternatively, the <literal + >countMessages()</literal> will return the number of messages in the queue + which <emphasis>match a given filter</emphasis></para> + </listitem> + <listitem> + <para>Changing message priority</para> + <para>The message priority can be changed by using the <literal + >changeMessagesPriority()</literal> method which returns a <literal + >boolean</literal> for the single message ID variant or the number of + updated messages for the filter variant.</para> + </listitem> + <listitem> + <para>Message counters</para> + <para>Message counters can be listed for a queue with the <literal + >listMessageCounter()</literal> and <literal + >listMessageCounterHistory()</literal> methods (see <xref + linkend="management.message-counters"/>)</para> + </listitem> + <listitem> + <para>Retrieving the queue attributes</para> + <para>The <literal>JMSQueueControl</literal> exposes JMS queue settings through + its attributes (e.g. <literal>isTemporary()</literal> to know whether the queue + is temporary or not, <literal>isDurable()</literal> to know whether the queue is + durable or not, etc.)</para> + </listitem> + <listitem> + <para>Pausing and resuming queues</para> + <para>The <literal>JMSQueueControl</literal> can pause and resume the underlying + queue. When the queue is paused it will continue to receive messages but will + not deliver them. When resumed again it will deliver the enqueued messages, if + any. </para> + </listitem> + </itemizedlist> + </section> + <section> + <title>JMS Topic Management</title> + <para>JMS Topics can be managed using the <literal>TopicControl</literal> class (with + the ObjectName <literal>org.hornetq:module=JMS,type=Topic,name="<the topic + name>"</literal> or the resource name <literal>jms.topic.<the topic + name></literal>).</para> + <itemizedlist> + <listitem> + <para>Listing subscriptions and messages</para> + <para>JMS topics subscriptions can be listed using the <literal + >listAllSubscriptions()</literal>, <literal + >listDurableSubscriptions()</literal>, <literal + >listNonDurableSubscriptions()</literal> methods. These methods return + arrays of <literal>Object</literal> representing the subscriptions information + (subscription name, client ID, durability, message count, etc.). It is also + possible to list the JMS messages for a given subscription with the <literal + >listMessagesForSubscription()</literal> method.</para> + </listitem> + <listitem> + <para>Dropping subscriptions</para> + <para>Durable subscriptions can be dropped from the topic using the <literal + >dropDurableSubscription()</literal> method.</para> + </listitem> + <listitem> + <para>Counting subscriptions messages</para> + <para>The <literal>countMessagesForSubscription()</literal> method can be used to + know the number of messages held for a given subscription (with an optional + message selector to know the number of messages matching the selector)</para> + </listitem> + </itemizedlist> + </section> + </section> + </section> + <section id="management.jmx"> + <title>Using Management Via JMX</title> + <para>HornetQ can be managed using <ulink + url="http://www.oracle.com/technetwork/java/javase/tech/javamanagement-140525.html"; + >JMX</ulink>. </para> + <para>The management API is exposed by HornetQ using MBeans interfaces. HornetQ registers its + resources with the domain <literal>org.hornetq</literal>.</para> + <para>For example, the <literal>ObjectName</literal> to manage a JMS Queue <literal + >exampleQueue</literal> is:</para> + <programlisting> +org.hornetq:module=JMS,type=Queue,name="exampleQueue"</programlisting> + <para>and the MBean is:</para> + <programlisting> +org.hornetq.api.jms.management.JMSQueueControl</programlisting> + <para>The MBean's <literal>ObjectName</literal> are built using the helper class <literal + >org.hornetq.api.core.management.ObjectNameBuilder</literal>. You can also use <literal + >jconsole</literal> to find the <literal>ObjectName</literal> of the MBeans you want to + manage. </para> + <para>Managing HornetQ using JMX is identical to management of any Java Applications using + JMX. It can be done by reflection or by creating proxies of the MBeans.</para> + <section id="management.jmx.configuration"> + <title>Configuring JMX</title> + <para>By default, JMX is enabled to manage HornetQ. It can be disabled by setting <literal + >jmx-management-enabled</literal> to <literal>false</literal> in <literal + >hornetq-configuration.xml</literal>:</para> + <programlisting> +<!-- false to disable JMX management for HornetQ --> +<jmx-management-enabled>false</jmx-management-enabled></programlisting> + <para>If JMX is enabled, HornetQ can be managed locally using <literal>jconsole</literal>.</para> + <note> + <para>Remote connections to JMX are not enabled by default for security reasons. Please refer + to <ulink url="http://docs.oracle.com/javase/6/docs/technotes/guides/management/agent.html"; + >Java Management guide</ulink> to configure the server for remote management (system + properties must be set in <literal>run.sh</literal> or <literal>run.bat</literal> + scripts).</para> + </note> + <para>By default, HornetQ server uses the JMX domain "org.hornetq". To manage several + HornetQ servers from the <emphasis>same</emphasis> MBeanServer, the JMX domain can be + configured for each individual HornetQ server by setting <literal>jmx-domain</literal> + in <literal>hornetq-configuration.xml</literal>: </para> + <programlisting> +<!-- use a specific JMX domain for HornetQ MBeans --> +<jmx-domain>my.org.hornetq</jmx-domain></programlisting> + <section> + <title>MBeanServer configuration</title> + <para>When HornetQ is run in standalone, it uses the Java Virtual Machine's <literal + >Platform MBeanServer</literal> to register its MBeans. This is configured in + JBoss Microcontainer Beans file (see <xref + linkend="server.microcontainer.configuration"/>):</para> + <programlisting> +<!-- MBeanServer --> +<bean name="MBeanServer" class="javax.management.MBeanServer"> + <constructor factoryClass="java.lang.management.ManagementFactory" + factoryMethod="getPlatformMBeanServer" /> +</bean></programlisting> + <para>When it is integrated in JBoss AS 5+, it uses the Application Server's own MBean + Server so that it can be managed using AS 5's jmx-console:</para> + <programlisting> +<!-- MBeanServer --> +<bean name="MBeanServer" class="javax.management.MBeanServer"> + <constructor factoryClass="org.jboss.mx.util.MBeanServerLocator" + factoryMethod="locateJBoss" /> +</bean></programlisting> + </section> + </section> + <section> + <title>Example</title> + <para>See <xref linkend="examples.jmx"/> for an example which shows how to use a remote + connection to JMX and MBean proxies to manage HornetQ.</para> + </section> + </section> + <section> + <title>Using Management Via Core API</title> + <para>The core management API in HornetQ is called by sending Core messages to a special + address, the <emphasis>management address</emphasis>.</para> + <para><emphasis>Management messages</emphasis> are regular Core messages with well-known + properties that the server needs to understand to interact with the management API:</para> + <itemizedlist> + <listitem> + <para>The name of the managed resource</para> + </listitem> + <listitem> + <para>The name of the management operation</para> + </listitem> + <listitem> + <para>The parameters of the management operation</para> + </listitem> + </itemizedlist> + <para>When such a management message is sent to the management address, HornetQ server will + handle it, extract the information, invoke the operation on the managed resources and send + a <emphasis>management reply</emphasis> to the management message's reply-to address + (specified by <literal>ClientMessageImpl.REPLYTO_HEADER_NAME</literal>). </para> + <para>A <literal>ClientConsumer</literal> can be used to consume the management reply and + retrieve the result of the operation (if any) stored in the reply's body. For portability, + results are returned as a <ulink url="http://json.org";>JSON</ulink> String rather than Java + Serialization (the <literal>org.hornetq.api.core.management.ManagementHelper</literal> can + be used to convert the JSON string to Java objects).</para> + <para>These steps can be simplified to make it easier to invoke management operations using + Core messages:</para> + <orderedlist> + <listitem> + <para>Create a <literal>ClientRequestor</literal> to send messages to the management + address and receive replies</para> + </listitem> + <listitem> + <para>Create a <literal>ClientMessage</literal></para> + </listitem> + <listitem> + <para>Use the helper class <literal + >org.hornetq.api.core.management.ManagementHelper</literal> to fill the message + with the management properties</para> + </listitem> + <listitem> + <para>Send the message using the <literal>ClientRequestor</literal></para> + </listitem> + <listitem> + <para>Use the helper class <literal + >org.hornetq.api.core.management.ManagementHelper</literal> to retrieve the + operation result from the management reply</para> + </listitem> + </orderedlist> + <para>For example, to find out the number of messages in the core queue <literal + >exampleQueue</literal>:</para> + <programlisting> +ClientSession session = ... +ClientRequestor requestor = new ClientRequestor(session, "jms.queue.hornetq.management"); +ClientMessage message = session.createMessage(false); +ManagementHelper.putAttribute(message, "core.queue.exampleQueue", "messageCount"); +session.start(); +ClientMessage reply = requestor.request(m); +int count = (Integer) ManagementHelper.getResult(reply); +System.out.println("There are " + count + " messages in exampleQueue");</programlisting> + <para>Management operation name and parameters must conform to the Java interfaces defined in + the <literal>management</literal> packages.</para> + <para>Names of the resources are built using the helper class <literal + >org.hornetq.api.core.management.ResourceNames</literal> and are straightforward + (<literal>core.queue.exampleQueue</literal> for the Core Queue <literal + >exampleQueue</literal>, <literal>jms.topic.exampleTopic</literal> for the JMS Topic + <literal>exampleTopic</literal>, etc.).</para> + <section id="management.core.configuration"> + <title>Configuring Core Management</title> + <para>The management address to send management messages is configured in <literal + >hornetq-configuration.xml</literal>:</para> + <programlisting> +<management-address>jms.queue.hornetq.management</management-address></programlisting> + <para>By default, the address is <literal>jms.queue.hornetq.management</literal> (it is + prepended by "jms.queue" so that JMS clients can also send management messages).</para> + <para>The management address requires a <emphasis>special</emphasis> user permission + <literal>manage</literal> to be able to receive and handle management messages. This + is also configured in hornetq-configuration.xml:</para> + <programlisting> +<!-- users with the admin role will be allowed to manage --> +<!-- HornetQ using management messages --> +<security-setting match="jms.queue.hornetq.management"> + <permission type="manage" roles="admin" /> +</security-setting></programlisting> + </section> + </section> + <section id="management.jms"> + <title>Using Management Via JMS</title> + <para>Using JMS messages to manage HornetQ is very similar to using core API.</para> + <para>An important difference is that JMS requires a JMS queue to send the messages to + (instead of an address for the core API).</para> + <para>The <emphasis>management queue</emphasis> is a special queue and needs to be + instantiated directly by the client:</para> + <programlisting> +Queue managementQueue = HornetQJMSClient.createQueue("hornetq.management");</programlisting> + <para>All the other steps are the same than for the Core API but they use JMS API + instead:</para> + <orderedlist> + <listitem> + <para>create a <literal>QueueRequestor</literal> to send messages to the management + address and receive replies</para> + </listitem> + <listitem> + <para>create a <literal>Message</literal></para> + </listitem> + <listitem> + <para>use the helper class <literal + >org.hornetq.api.jms.management.JMSManagementHelper</literal> to fill the message + with the management properties</para> + </listitem> + <listitem> + <para>send the message using the <literal>QueueRequestor</literal></para> + </listitem> + <listitem> + <para>use the helper class <literal + >org.hornetq.api.jms.management.JMSManagementHelper</literal> to retrieve the + operation result from the management reply</para> + </listitem> + </orderedlist> + <para>For example, to know the number of messages in the JMS queue <literal + >exampleQueue</literal>:</para> + <programlisting> +Queue managementQueue = HornetQJMSClient.createQueue("hornetq.management"); + +QueueSession session = ... +QueueRequestor requestor = new QueueRequestor(session, managementQueue); +connection.start(); +Message message = session.createMessage(); +JMSManagementHelper.putAttribute(message, "jms.queue.exampleQueue", "messageCount"); +Message reply = requestor.request(message); +int count = (Integer)JMSManagementHelper.getResult(reply); +System.out.println("There are " + count + " messages in exampleQueue");</programlisting> + <section> + <title>Configuring JMS Management</title> + <para>Whether JMS or the core API is used for management, the configuration steps are the + same (see <xref linkend="management.core.configuration"/>).</para> + </section> + <section> + <title>Example</title> + <para>See <xref linkend="examples.management"/> for an example which shows how to use JMS + messages to manage HornetQ server.</para> + </section> + </section> + + <section id="management.notifications"> + <title>Management Notifications</title> + <para>HornetQ emits <emphasis>notifications</emphasis> to inform listeners of potentially + interesting events (creation of new resources, security violation, etc.).</para> + <para>These notifications can be received by 3 different ways:</para> + <itemizedlist> + <listitem> + <para>JMX notifications</para> + </listitem> + <listitem> + <para>Core messages</para> + </listitem> + <listitem> + <para>JMS messages</para> + </listitem> + </itemizedlist> + <section> + <title>JMX Notifications</title> + <para>If JMX is enabled (see <xref linkend="management.jmx.configuration"/>), JMX + notifications can be received by subscribing to 2 MBeans:</para> + <itemizedlist> + <listitem> + <para><literal>org.hornetq:module=Core,type=Server</literal> for notifications on + <emphasis>Core</emphasis> resources</para> + </listitem> + <listitem> + <para><literal>org.hornetq:module=JMS,type=Server</literal> for notifications on + <emphasis>JMS</emphasis> resources</para> + </listitem> + </itemizedlist> + </section> + <section> + <title>Core Messages Notifications</title> + <para>HornetQ defines a special <emphasis>management notification address</emphasis>. Core + queues can be bound to this address so that clients will receive management + notifications as Core messages</para> + <para>A Core client which wants to receive management notifications must create a core + queue bound to the management notification address. It can then receive the + notifications from its queue.</para> + <para>Notifications messages are regular core messages with additional properties + corresponding to the notification (its type, when it occurred, the resources which were + concerned, etc.).</para> + <para>Since notifications are regular core messages, it is possible to use message + selectors to filter out notifications and receives only a subset of all the + notifications emitted by the server.</para> + <section id="management.notifications.core.configuration"> + <title>Configuring The Core Management Notification Address</title> + <para>The management notification address to receive management notifications is + configured in <literal>hornetq-configuration.xml</literal>:</para> + <programlisting> +<management-notification-address>hornetq.notifications</management-notification-address></programlisting> + <para>By default, the address is <literal>hornetq.notifications</literal>.</para> + </section> + </section> + <section> + <title>JMS Messages Notifications</title> + <para>HornetQ's notifications can also be received using JMS messages.</para> + <para>It is similar to receiving notifications using Core API but an important difference + is that JMS requires a JMS Destination to receive the messages (preferably a + Topic).</para> + <para>To use a JMS Destination to receive management notifications, you must change the server's + management notification address to start with <literal>jms.queue</literal> if it is a JMS Queue + or <literal>jms.topic</literal> if it is a JMS Topic:</para> + <programlisting> +<!-- notifications will be consumed from "notificationsTopic" JMS Topic --> +<management-notification-address>jms.topic.notificationsTopic</management-notification-address></programlisting> + <para>Once the notification topic is created, you can receive messages from it or set a + <literal>MessageListener</literal>:</para> + <programlisting> +Topic notificationsTopic = HornetQJMSClient.createTopic("notificationsTopic"); + +Session session = ... +MessageConsumer notificationConsumer = session.createConsumer(notificationsTopic); +notificationConsumer.setMessageListener(new MessageListener() +{ + public void onMessage(Message notif) + { + System.out.println("------------------------"); + System.out.println("Received notification:"); + try + { + Enumeration propertyNames = notif.getPropertyNames(); + while (propertyNames.hasMoreElements()) + { + String propertyName = (String)propertyNames.nextElement(); + System.out.format(" %s: %s\n", propertyName, notif.getObjectProperty(propertyName)); + } + } + catch (JMSException e) + { + } + System.out.println("------------------------"); + } +});</programlisting> + </section> + <section> + <title>Example</title> + <para>See <xref linkend="examples.management-notifications"/> for an example which shows + how to use a JMS <literal>MessageListener</literal> to receive management notifications + from HornetQ server.</para> + </section> + <section> + <title>Notification Types and Headers</title> + <para>Below is a list of all the different kinds of notifications as well as which headers are + on the messages. Every notification has a <literal>_HQ_NotifType</literal> (value noted in parentheses) + and <literal>_HQ_NotifTimestamp</literal> header. The timestamp is the un-formatted result of a call + to <literal>java.lang.System.currentTimeMillis()</literal>.</para> + <itemizedlist> + <listitem> + <para><literal>BINDING_ADDED</literal> (0)</para> + <para><literal>_HQ_Binding_Type</literal>, <literal>_HQ_Address</literal>, + <literal>_HQ_ClusterName</literal>, <literal>_HQ_RoutingName</literal>, + <literal>_HQ_Binding_ID</literal>, <literal>_HQ_Distance</literal>, + <literal>_HQ_FilterString</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>BINDING_REMOVED</literal> (1)</para> + <para><literal>_HQ_Address</literal>, <literal>_HQ_ClusterName</literal>, + <literal>_HQ_RoutingName</literal>, <literal>_HQ_Binding_ID</literal>, + <literal>_HQ_Distance</literal>, <literal>_HQ_FilterString</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>CONSUMER_CREATED</literal> (2)</para> + <para><literal>_HQ_Address</literal>, <literal>_HQ_ClusterName</literal>, + <literal>_HQ_RoutingName</literal>, <literal>_HQ_Distance</literal>, + <literal>_HQ_ConsumerCount</literal>, <literal>_HQ_User</literal>, + <literal>_HQ_RemoteAddress</literal>, <literal>_HQ_SessionName</literal>, + <literal>_HQ_FilterString</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>CONSUMER_CLOSED</literal> (3)</para> + <para><literal>_HQ_Address</literal>, <literal>_HQ_ClusterName</literal>, + <literal>_HQ_RoutingName</literal>, <literal>_HQ_Distance</literal>, + <literal>_HQ_ConsumerCount</literal>, <literal>_HQ_User</literal>, + <literal>_HQ_RemoteAddress</literal>, <literal>_HQ_SessionName</literal>, + <literal>_HQ_FilterString</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>SECURITY_AUTHENTICATION_VIOLATION</literal> (6)</para> + <para><literal>_HQ_User</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>SECURITY_PERMISSION_VIOLATION</literal> (7)</para> + <para><literal>_HQ_Address</literal>, <literal>_HQ_CheckType</literal>, + <literal>_HQ_User</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>DISCOVERY_GROUP_STARTED</literal> (8)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>DISCOVERY_GROUP_STOPPED</literal> (9)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>BROADCAST_GROUP_STARTED</literal> (10)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>BROADCAST_GROUP_STOPPED</literal> (11)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>BRIDGE_STARTED</literal> (12)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>BRIDGE_STOPPED</literal> (13)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>CLUSTER_CONNECTION_STARTED</literal> (14)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>CLUSTER_CONNECTION_STOPPED</literal> (15)</para> + <para><literal>name</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>ACCEPTOR_STARTED</literal> (16)</para> + <para><literal>factory</literal>, <literal>id</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>ACCEPTOR_STOPPED</literal> (17)</para> + <para><literal>factory</literal>, <literal>id</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>PROPOSAL</literal> (18)</para> + <para><literal>_JBM_ProposalGroupId</literal>, <literal>_JBM_ProposalValue</literal>, + <literal>_HQ_Binding_Type</literal>, <literal>_HQ_Address</literal>, + <literal>_HQ_Distance</literal></para> + </listitem> + </itemizedlist> + <itemizedlist> + <listitem> + <para><literal>PROPOSAL_RESPONSE</literal> (19)</para> + <para><literal>_JBM_ProposalGroupId</literal>, <literal>_JBM_ProposalValue</literal>, + <literal>_JBM_ProposalAltValue</literal>, <literal>_HQ_Binding_Type</literal>, + <literal>_HQ_Address</literal>, <literal>_HQ_Distance</literal></para> + </listitem> + </itemizedlist> + </section> + </section> + <section id="management.message-counters"> + <title>Message Counters</title> + <para>Message counters can be used to obtain information on queues <emphasis>over + time</emphasis> as HornetQ keeps a history on queue metrics.</para> + <para>They can be used to show <emphasis>trends</emphasis> on queues. For example, using the + management API, it would be possible to query the number of messages in a queue at regular + interval. However, this would not be enough to know if the queue is used: the number of + messages can remain constant because nobody is sending or receiving messages from the queue + or because there are as many messages sent to the queue than messages consumed from it. The + number of messages in the queue remains the same in both cases but its use is widely + different.</para> + <para>Message counters gives additional information about the queues:</para> + <itemizedlist> + <listitem> + <para><literal>count</literal></para> + <para>The <emphasis>total</emphasis> number of messages added to the queue since the + server was started</para> + </listitem> + <listitem> + <para><literal>countDelta</literal></para> + <para>the number of messages added to the queue <emphasis>since the last message counter + update</emphasis></para> + </listitem> + <listitem> + <para><literal>messageCount</literal></para> + <para>The <emphasis>current</emphasis> number of messages in the queue</para> + </listitem> + <listitem> + <para><literal>messageCountDelta</literal></para> + <para>The <emphasis>overall</emphasis> number of messages added/removed from the queue + <emphasis>since the last message counter update</emphasis>. For example, if + <literal>messageCountDelta</literal> is equal to <literal>-10</literal> this means that + overall 10 messages have been removed from the queue (e.g. 2 messages were added and + 12 were removed)</para> + </listitem> + <listitem> + <para><literal>lastAddTimestamp</literal></para> + <para>The timestamp of the last time a message was added to the queue</para> + </listitem> + <listitem> + <para><literal>udpateTimestamp</literal></para> + <para>The timestamp of the last message counter update</para> + </listitem> + </itemizedlist> + <para>These attributes can be used to determine other meaningful data as well. For example, to know + specifically how many messages were <emphasis>consumed</emphasis> from the queue since the last update + simply subtract the <literal>messageCountDelta</literal> from <literal>countDelta</literal>.</para> + <section id="configuring.message.counters"> + <title>Configuring Message Counters</title> + <para>By default, message counters are disabled as it might have a small negative effect on + memory.</para> + <para>To enable message counters, you can set it to <literal>true</literal> in <literal + >hornetq-configuration.xml</literal>:</para> + <programlisting> +<message-counter-enabled>true</message-counter-enabled></programlisting> + <para>Message counters keeps a history of the queue metrics (10 days by default) and + samples all the queues at regular interval (10 seconds by default). If message counters + are enabled, these values should be configured to suit your messaging use case in + <literal>hornetq-configuration.xml</literal>:</para> + <programlisting> +<!-- keep history for a week --> +<message-counter-max-day-history>7</message-counter-max-day-history> +<!-- sample the queues every minute (60000ms) --> +<message-counter-sample-period>60000</message-counter-sample-period></programlisting> + <para>Message counters can be retrieved using the Management API. For example, to retrieve + message counters on a JMS Queue using JMX:</para> + <programlisting> +// retrieve a connection to HornetQ's MBeanServer +MBeanServerConnection mbsc = ... +JMSQueueControlMBean queueControl = (JMSQueueControl)MBeanServerInvocationHandler.newProxyInstance(mbsc, + on, + JMSQueueControl.class, + false); +// message counters are retrieved as a JSON String +String counters = queueControl.listMessageCounter(); +// use the MessageCounterInfo helper class to manipulate message counters more easily +MessageCounterInfo messageCounter = MessageCounterInfo.fromJSON(counters); +System.out.format("%s message(s) in the queue (since last sample: %s)\n", +messageCounter.getMessageCount(), +messageCounter.getMessageCountDelta());</programlisting> + </section> + <section> + <title>Example</title> + <para>See <xref linkend="examples.message-counters"/> for an example which shows how to use + message counters to retrieve information on a JMS <literal>Queue</literal>.</para> + </section> + </section> + <section> + <title>Administering HornetQ Resources Using The JBoss AS Admin Console</title> + <para>Its possible to create and configure HornetQ resources via the admin console within the JBoss Application Server.</para> + <para>The Admin Console will allow you to create destinations (JMS Topics and Queues) and JMS Connection Factories.</para> + <para>Once logged in to the admin console you will see a JMS Manager item in the left hand tree. All HornetQ resources + will be configured via this. This will have a child items for JMS Queues, Topics and Connection Factories, clicking + on each node will reveal which resources are currently available. The following sections explain how to create + and configure each resource in turn.</para> + <section> + <title>JMS Queues</title> + <para>To create a new JMS Queue click on the JMS Queues item to reveal the available queues. On the right hand + panel you will see an add a new resource button, click on this and then choose the default(JMS Queue) template + and click continue. The important things to fill in here are the name of the queue and the JNDI name of the + queue. The JNDI name is what you will use to look up the queue in JNDI from your client. For most queues this + will be the only info you will need to provide as sensible defaults are provided for the others. You will also + see a security roles section near the bottom. If you do not provide any roles for this queue then the servers + default security configuration will be used, after you have created the queue these will be shown in the configuration. + All configuration values, except the name and JNDI name, can be changed via the configuration tab after clicking + on the queue in the admin console. The following section explains these in more detail</para> + <para>After highlighting the configuration you will see the following screen</para> + <para> + <graphic fileref="images/console1.png" scalefit="1" width="500" align="center"/> + </para> + <para>The name and JNDI name can't be changed, if you want to change these recreate the queue with the appropriate + settings. The rest of the configuration options, apart from security roles, relate to address settings for a particular + address. The default address settings are picked up from the servers configuration, if you change any of these + settings or create a queue via the console a new Address Settings entry will be added. For a full explanation on + Address Settings see <xref linkend="queue-attributes.address-settings"/></para> + <para>To delete a queue simply click on the delete button beside the queue name in the main JMS Queues screen. + This will also delete any address settings or security settings previously created for the queues address</para> + <para>The last part of the configuration options are security roles. If non are provided on creation then the + servers default security settings will be shown. If these are changed or updated then new security settings are + created for the address of this queue. For more information on security setting see <xref linkend="security"/> </para> + <para>It is also possible via the metrics tab to view statistics for this queue. This will show statistics such + as message count, consumer count etc.</para> + <para>Operations can be performed on a queue via the control tab. This will allow you to start and stop the queue, + list,move,expire and delete messages from the queue and other useful operations. To invoke an operation click on + the button for the operation you want, this will take you to a screen where you can parameters for the operation can be set. + Once set clicking the ok button will invoke the operation, results appear at the bottom of the screen.</para> + </section> + <section> + <title>JMS Topics</title> + <para>Creating and configuring JMS Topics is almost identical to creating queues. The only difference is that the + configuration will be applied to the queue representing a subscription.</para> + </section> + <section> + <title>JMS Connection Factories</title> + <para>The format for creating connection factories is the same as for JMS Queues and topics apart from the configuration + being different. For as list of all the connection factory settings see the configuration index </para> + </section> + </section> +</chapter>
http://git-wip-us.apache.org/repos/asf/activemq-6/blob/8ecd255f/docs/user-manual/en/message-expiry.xml ---------------------------------------------------------------------- diff --git a/docs/user-manual/en/message-expiry.xml b/docs/user-manual/en/message-expiry.xml new file mode 100644 index 0000000..e4d1f37 --- /dev/null +++ b/docs/user-manual/en/message-expiry.xml @@ -0,0 +1,101 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!-- ============================================================================= --> +<!-- Copyright © 2009 Red Hat, Inc. and others. --> +<!-- --> +<!-- The text of and illustrations in this document are licensed by Red Hat under --> +<!-- a Creative Commons AttributionâShare Alike 3.0 Unported license ("CC-BY-SA"). --> +<!-- --> +<!-- An explanation of CC-BY-SA is available at --> +<!-- --> +<!-- http://creativecommons.org/licenses/by-sa/3.0/. --> +<!-- --> +<!-- In accordance with CC-BY-SA, if you distribute this document or an adaptation --> +<!-- of it, you must provide the URL for the original version. --> +<!-- --> +<!-- Red Hat, as the licensor of this document, waives the right to enforce, --> +<!-- and agrees not to assert, Section 4d of CC-BY-SA to the fullest extent --> +<!-- permitted by applicable law. --> +<!-- ============================================================================= --> + +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd"; [ +<!ENTITY % BOOK_ENTITIES SYSTEM "HornetQ_User_Manual.ent"> +%BOOK_ENTITIES; +]> +<chapter id="message-expiry"> + <title>Message Expiry</title> + <para>Messages can be set with an optional <emphasis>time to live</emphasis> when sending + them.</para> + <para>HornetQ will not deliver a message to a consumer after it's time to live has been exceeded. + If the message hasn't been delivered by the time that time to live is reached the server can + discard it.</para> + <para>HornetQ's addresses can be assigned a expiry address so that, when messages are expired, + they are removed from the queue and sent to the expiry address. Many different queues can be + bound to an expiry address. These <emphasis>expired</emphasis> messages can later be consumed + for further inspection.</para> + <section> + <title>Message Expiry</title> + <para>Using HornetQ Core API, you can set an expiration time directly on the message:</para> + <programlisting> +// message will expire in 5000ms from now +message.setExpiration(System.currentTimeMillis() + 5000);</programlisting> + <para>JMS MessageProducer allows to set a TimeToLive for the messages it sent:</para> + <programlisting> +// messages sent by this producer will be retained for 5s (5000ms) before expiration +producer.setTimeToLive(5000);</programlisting> + <para>Expired messages which are consumed from an expiry address have the following + properties:</para> + <itemizedlist> + <listitem> + <para><literal>_HQ_ORIG_ADDRESS</literal></para> + <para>a String property containing the <emphasis>original address</emphasis> of the + expired message </para> + </listitem> + <listitem> + <para><literal>_HQ_ORIG_QUEUE</literal></para> + <para>a String property containing the <emphasis>original queue</emphasis> of the + expired message </para> + </listitem> + <listitem> + <para><literal>_HQ_ACTUAL_EXPIRY</literal></para> + <para>a Long property containing the <emphasis>actual expiration time</emphasis> of the + expired message</para> + </listitem> + </itemizedlist> + </section> + <section id="message-expiry.configuring"> + <title>Configuring Expiry Addresses</title> + <para>Expiry address are defined in the address-setting configuration:</para> + <programlisting> +<!-- expired messages in exampleQueue will be sent to the expiry address expiryQueue --> +<address-setting match="jms.queue.exampleQueue"> + <expiry-address>jms.queue.expiryQueue</expiry-address> +</address-setting></programlisting> + <para>If messages are expired and no expiry address is specified, messages are simply removed + from the queue and dropped. Address wildcards can be used to configure expiry address for a + set of addresses (see <xref linkend="wildcard-syntax"/>).</para> + </section> + <section id="configuring.expiry.reaper"> + <title>Configuring The Expiry Reaper Thread</title> + <para>A reaper thread will periodically inspect the queues to check if messages have + expired.</para> + <para>The reaper thread can be configured with the following properties in <literal + >hornetq-configuration.xml</literal></para> + <itemizedlist> + <listitem> + <para><literal>message-expiry-scan-period</literal></para> + <para>How often the queues will be scanned to detect expired messages (in milliseconds, + default is 30000ms, set to <literal>-1</literal> to disable the reaper thread)</para> + </listitem> + <listitem> + <para><literal>message-expiry-thread-priority</literal></para> + <para>The reaper thread priority (it must be between 0 and 9, 9 being the highest + priority, default is 3)</para> + </listitem> + </itemizedlist> + </section> + <section> + <title>Example</title> + <para>See <xref linkend="examples.expiry"/> for an example which shows how message expiry is + configured and used with JMS.</para> + </section> +</chapter>
