919 lines
35 KiB
Markdown
919 lines
35 KiB
Markdown
Examples
|
|
========
|
|
|
|
The Apache ActiveMQ Artemis distribution comes with over 90 run out-of-the-box examples
|
|
demonstrating many of the features.
|
|
|
|
The examples are available in both the binary and source distribution under the `examples`
|
|
directory. Examples are split by the following source tree:
|
|
|
|
- features - Examples containing broker specific features.
|
|
- ha - examples showing failover and reconnection capabilities.
|
|
- clustered - examples showing load balancing and distribution capabilities.
|
|
- perf - examples allowing you to run a few performance tests on the server
|
|
- sub-modules - examples of integrated external modules.
|
|
- protocols - Protocol specific examples
|
|
- openwire
|
|
- mqtt
|
|
- stomp
|
|
- amqp
|
|
|
|
A set of Java EE examples are also provided which need WildFly installed
|
|
to be able to run.
|
|
|
|
Examples
|
|
========
|
|
|
|
To run any example, simply `cd` into the appropriate example directory
|
|
and type `mvn verify` or `mvn install` (For details please read the readme.html in each
|
|
example directory).
|
|
|
|
You can use the profile -Pexamples to run multiple examples under any example tree.
|
|
|
|
For each server, you will have a created server under ./target/server0 (some examples use more than one server).
|
|
|
|
You have the option to disable the server running (say if you want to start the server manually) by simply specifying the -PnoServer profile
|
|
|
|
|
|
This will run the example without a server:
|
|
|
|
``` sh
|
|
# running an example without running the server
|
|
mvn verify -PnoServer
|
|
```
|
|
|
|
Also under ./target there will be a script repeating the commands to create each server:
|
|
|
|
Example this is create-server0.sh created for the queue example. It could be useful to see what we do on the example:
|
|
```sh
|
|
# These are the commands used to create server0
|
|
/myInstallDirectory/apache-artemis-1.1.0/bin/artemis create --allow-anonymous --silent --force --no-web --user guest --password guest --role guest --port-offset 0 --data ./data --allow-anonymous --no-autotune --verbose /myInstallDirectory/apache-artemis-1.1.0/examples/features/standard/queue/target/server0
|
|
```
|
|
|
|
These examples are all using the [Maven plugin](maven-plugin.md), which can be useful for running your test servers as well.
|
|
|
|
This is the common output when running an example. On this case taken from the Queue example:
|
|
|
|
|
|
```sh
|
|
[INFO] Scanning for projects...
|
|
[INFO]
|
|
[INFO] ------------------------------------------------------------------------
|
|
[INFO] Building ActiveMQ Artemis JMS Queue Example 1.1.0
|
|
[INFO] ------------------------------------------------------------------------
|
|
[INFO]
|
|
[INFO] --- maven-enforcer-plugin:1.4:enforce (enforce-java) @ queue ---
|
|
[INFO]
|
|
[INFO] --- maven-remote-resources-plugin:1.5:process (default) @ queue ---
|
|
[INFO]
|
|
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ queue ---
|
|
[INFO] Using 'UTF-8' encoding to copy filtered resources.
|
|
[INFO] Copying 1 resource
|
|
[INFO] Copying 3 resources
|
|
[INFO]
|
|
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ queue ---
|
|
[INFO] Changes detected - recompiling the module!
|
|
[INFO] Compiling 1 source file to /work/apache-artemis-1.1.0/examples/features/standard/queue/target/classes
|
|
[INFO]
|
|
[INFO] --- maven-checkstyle-plugin:2.16:check (default) @ queue ---
|
|
[INFO]
|
|
[INFO] --- apache-rat-plugin:0.11:check (default) @ queue ---
|
|
[INFO] RAT will not execute since it is configured to be skipped via system property 'rat.skip'.
|
|
[INFO]
|
|
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ queue ---
|
|
[INFO] Using 'UTF-8' encoding to copy filtered resources.
|
|
[INFO] skip non existing resourceDirectory /work/apache-artemis-1.1.0/examples/features/standard/queue/src/test/resources
|
|
[INFO] Copying 3 resources
|
|
[INFO]
|
|
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ queue ---
|
|
[INFO] No sources to compile
|
|
[INFO]
|
|
[INFO] --- maven-surefire-plugin:2.18.1:test (default-test) @ queue ---
|
|
[INFO]
|
|
[INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ queue ---
|
|
[INFO] Building jar: /work/apache-artemis-1.1.0/examples/features/standard/queue/target/queue-1.1.0.jar
|
|
[INFO]
|
|
[INFO] --- maven-site-plugin:3.3:attach-descriptor (attach-descriptor) @ queue ---
|
|
[INFO]
|
|
[INFO] >>> maven-source-plugin:2.2.1:jar (attach-sources) > generate-sources @ queue >>>
|
|
[INFO]
|
|
[INFO] --- maven-enforcer-plugin:1.4:enforce (enforce-java) @ queue ---
|
|
[INFO]
|
|
[INFO] <<< maven-source-plugin:2.2.1:jar (attach-sources) < generate-sources @ queue <<<
|
|
[INFO]
|
|
[INFO] --- maven-source-plugin:2.2.1:jar (attach-sources) @ queue ---
|
|
[INFO] Building jar: /work/apache-artemis-1.1.0/examples/features/standard/queue/target/queue-1.1.0-sources.jar
|
|
[INFO]
|
|
[INFO] >>> maven-source-plugin:2.2.1:jar (default) > generate-sources @ queue >>>
|
|
[INFO]
|
|
[INFO] --- maven-enforcer-plugin:1.4:enforce (enforce-java) @ queue ---
|
|
[INFO]
|
|
[INFO] <<< maven-source-plugin:2.2.1:jar (default) < generate-sources @ queue <<<
|
|
[INFO]
|
|
[INFO] --- maven-source-plugin:2.2.1:jar (default) @ queue ---
|
|
[INFO]
|
|
[INFO] --- artemis-maven-plugin:1.1.0:create (create) @ queue ---
|
|
[INFO] Local id: local
|
|
url: file:///Users/apacheuser/.m2/repository/
|
|
layout: default
|
|
snapshots: [enabled => true, update => always]
|
|
releases: [enabled => true, update => always]
|
|
|
|
[INFO] Entries.size 2
|
|
[INFO] ... key=project = MavenProject: org.apache.activemq.examples.broker:queue:1.1.0 @ /work/apache-artemis-1.1.0/examples/features/standard/queue/pom.xml
|
|
[INFO] ... key=pluginDescriptor = Component Descriptor: role: 'org.apache.maven.plugin.Mojo', implementation: 'org.apache.activemq.artemis.maven.ArtemisCLIPlugin', role hint: 'org.apache.activemq:artemis-maven-plugin:1.1.0:cli'
|
|
role: 'org.apache.maven.plugin.Mojo', implementation: 'org.apache.activemq.artemis.maven.ArtemisCreatePlugin', role hint: 'org.apache.activemq:artemis-maven-plugin:1.1.0:create'
|
|
role: 'org.apache.maven.plugin.Mojo', implementation: 'org.apache.activemq.artemis.maven.ArtemisClientPlugin', role hint: 'org.apache.activemq:artemis-maven-plugin:1.1.0:runClient'
|
|
---
|
|
Executing org.apache.activemq.artemis.cli.commands.Create create --allow-anonymous --silent --force --no-web --user guest --password guest --role guest --port-offset 0 --data ./data --allow-anonymous --no-autotune --verbose /work/apache-artemis-1.1.0/examples/features/standard/queue/target/server0
|
|
Home::/work/apache-artemis-1.1.0/examples/features/standard/queue/../../../.., Instance::.
|
|
Creating ActiveMQ Artemis instance at: /work/apache-artemis-1.1.0/examples/features/standard/queue/target/server0
|
|
|
|
You can now start the broker by executing:
|
|
|
|
"/work/apache-artemis-1.1.0/examples/features/standard/queue/target/server0/bin/artemis" run
|
|
|
|
Or you can run the broker in the background using:
|
|
|
|
"/work/apache-artemis-1.1.0/examples/features/standard/queue/target/server0/bin/artemis-service" start
|
|
|
|
[INFO] ###################################################################################################
|
|
[INFO] create-server0.sh created with commands to reproduce server0
|
|
[INFO] under /work/apache-artemis-1.1.0/examples/features/standard/queue/target
|
|
[INFO] ###################################################################################################
|
|
[INFO]
|
|
[INFO] --- artemis-maven-plugin:1.1.0:cli (start) @ queue ---
|
|
[INFO] awaiting server to start
|
|
[INFO] awaiting server to start
|
|
server-out: _ _ _
|
|
server-out: / \ ____| |_ ___ __ __(_) _____
|
|
server-out: / _ \| _ \ __|/ _ \ \/ | |/ __/
|
|
server-out: / ___ \ | \/ |_/ __/ |\/| | |\___ \
|
|
server-out: /_/ \_\| \__\____|_| |_|_|/___ /
|
|
server-out: Apache ActiveMQ Artemis 1.1.0
|
|
server-out:
|
|
server-out:
|
|
server-out:17:30:25,091 INFO [org.apache.activemq.artemis.integration.bootstrap] AMQ101000: Starting ActiveMQ Artemis Server
|
|
server-out:17:30:25,120 INFO [org.apache.activemq.artemis.core.server] AMQ221000: live Message Broker is starting with configuration Broker Configuration (clustered=false,journalDirectory=./data/journal,bindingsDirectory=./data/bindings,largeMessagesDirectory=./data/large-messages,pagingDirectory=./data/paging)
|
|
server-out:17:30:25,152 INFO [org.apache.activemq.artemis.core.server] AMQ221013: Using NIO Journal
|
|
server-out:17:30:25,195 INFO [org.apache.activemq.artemis.core.server] AMQ221043: Protocol module found: [artemis-server]. Adding protocol support for: CORE
|
|
server-out:17:30:25,199 INFO [org.apache.activemq.artemis.core.server] AMQ221043: Protocol module found: [artemis-amqp-protocol]. Adding protocol support for: AMQP
|
|
server-out:17:30:25,209 INFO [org.apache.activemq.artemis.core.server] AMQ221043: Protocol module found: [artemis-hornetq-protocol]. Adding protocol support for: HORNETQ
|
|
server-out:17:30:25,211 INFO [org.apache.activemq.artemis.core.server] AMQ221043: Protocol module found: [artemis-mqtt-protocol]. Adding protocol support for: MQTT
|
|
server-out:17:30:25,214 INFO [org.apache.activemq.artemis.core.server] AMQ221043: Protocol module found: [artemis-openwire-protocol]. Adding protocol support for: OPENWIRE
|
|
server-out:17:30:25,335 INFO [org.apache.activemq.artemis.core.server] AMQ221043: Protocol module found: [artemis-stomp-protocol]. Adding protocol support for: STOMP
|
|
[INFO] awaiting server to start
|
|
server-out:17:30:25,781 INFO [org.apache.activemq.artemis.core.server] AMQ221003: trying to deploy queue jms.queue.DLQ
|
|
server-out:17:30:25,835 INFO [org.apache.activemq.artemis.core.server] AMQ221003: trying to deploy queue jms.queue.ExpiryQueue
|
|
server-out:17:30:25,933 INFO [org.apache.activemq.artemis.core.server] AMQ221020: Started Acceptor at 0.0.0.0:61616 for protocols [CORE,MQTT,AMQP,HORNETQ,STOMP,OPENWIRE]
|
|
server-out:17:30:25,936 INFO [org.apache.activemq.artemis.core.server] AMQ221020: Started Acceptor at 0.0.0.0:5445 for protocols [HORNETQ,STOMP]
|
|
server-out:17:30:25,939 INFO [org.apache.activemq.artemis.core.server] AMQ221020: Started Acceptor at 0.0.0.0:5672 for protocols [AMQP]
|
|
server-out:17:30:25,944 INFO [org.apache.activemq.artemis.core.server] AMQ221020: Started Acceptor at 0.0.0.0:1883 for protocols [MQTT]
|
|
server-out:17:30:25,948 INFO [org.apache.activemq.artemis.core.server] AMQ221020: Started Acceptor at 0.0.0.0:61613 for protocols [STOMP]
|
|
server-out:17:30:25,949 INFO [org.apache.activemq.artemis.core.server] AMQ221007: Server is now live
|
|
server-out:17:30:25,949 INFO [org.apache.activemq.artemis.core.server] AMQ221001: Apache ActiveMQ Artemis Message Broker version 1.1.0 [nodeID=a855176b-50f0-11e5-937e-2fe9bb000966]
|
|
[INFO] Server started
|
|
[INFO]
|
|
[INFO] --- artemis-maven-plugin:1.1.0:runClient (runClient) @ queue ---
|
|
Sent message: This is a text message
|
|
Received message: This is a text message
|
|
[INFO]
|
|
[INFO] --- artemis-maven-plugin:1.1.0:cli (stop) @ queue ---
|
|
server-out:17:30:27,476 INFO [org.apache.activemq.artemis.core.server] AMQ221002: Apache ActiveMQ Artemis Message Broker version 1.0.1-SNA
|
|
[INFO] ------------------------------------------------------------------------
|
|
[INFO] BUILD SUCCESS
|
|
[INFO] ------------------------------------------------------------------------
|
|
[INFO] Total time: 7.840 s
|
|
[INFO] Finished at: 2015-09-01T17:30:27-04:00
|
|
[INFO] Final Memory: 42M/508M
|
|
[INFO] ------------------------------------------------------------------------
|
|
|
|
```
|
|
|
|
Applet
|
|
------
|
|
|
|
This example shows you how to send and receive JMS messages from an
|
|
Applet.
|
|
|
|
Application-Layer Failover
|
|
--------------------------
|
|
|
|
Apache ActiveMQ Artemis also supports Application-Layer failover, useful in the case
|
|
that replication is not enabled on the server side.
|
|
|
|
With Application-Layer failover, it's up to the application to register
|
|
a JMS `ExceptionListener` with Apache ActiveMQ Artemis which will be called by Apache ActiveMQ Artemis
|
|
in the event that connection failure is detected.
|
|
|
|
The code in the `ExceptionListener` then recreates the JMS connection,
|
|
session, etc on another node and the application can continue.
|
|
|
|
Application-layer failover is an alternative approach to High
|
|
Availability (HA). Application-layer failover differs from automatic
|
|
failover in that some client side coding is required in order to
|
|
implement this. Also, with Application-layer failover, since the old
|
|
session object dies and a new one is created, any uncommitted work in
|
|
the old session will be lost, and any unacknowledged messages might be
|
|
redelivered.
|
|
|
|
Core Bridge Example
|
|
-------------------
|
|
|
|
The `bridge` example demonstrates a core bridge deployed on one server,
|
|
which consumes messages from a local queue and forwards them to an
|
|
address on a second server.
|
|
|
|
Core bridges are used to create message flows between any two Apache ActiveMQ Artemis
|
|
servers which are remotely separated. Core bridges are resilient and
|
|
will cope with temporary connection failure allowing them to be an ideal
|
|
choice for forwarding over unreliable connections, e.g. a WAN.
|
|
|
|
Browser
|
|
-------
|
|
|
|
The `browser` example shows you how to use a JMS `QueueBrowser` with
|
|
Apache ActiveMQ Artemis.
|
|
|
|
Queues are a standard part of JMS, please consult the JMS 1.1
|
|
specification for full details.
|
|
|
|
A `QueueBrowser` is used to look at messages on the queue without
|
|
removing them. It can scan the entire content of a queue or only
|
|
messages matching a message selector.
|
|
|
|
Client Kickoff
|
|
--------------
|
|
|
|
The `client-kickoff` example shows how to terminate client connections
|
|
given an IP address using the JMX management API.
|
|
|
|
Client side failover listener
|
|
-----------------------------
|
|
|
|
The `client-side-failoverlistener` example shows how to register a
|
|
listener to monitor failover events
|
|
|
|
Client-Side Load-Balancing
|
|
--------------------------
|
|
|
|
The `client-side-load-balancing` example demonstrates how sessions
|
|
created from a single JMS `Connection` can be created to different nodes
|
|
of the cluster. In other words it demonstrates how Apache ActiveMQ Artemis does
|
|
client-side load-balancing of sessions across the cluster.
|
|
|
|
Clustered Durable Subscription
|
|
------------------------------
|
|
|
|
This example demonstrates a clustered JMS durable subscription
|
|
|
|
Clustered Grouping
|
|
------------------
|
|
|
|
This is similar to the message grouping example except that it
|
|
demonstrates it working over a cluster. Messages sent to different nodes
|
|
with the same group id will be sent to the same node and the same
|
|
consumer.
|
|
|
|
Clustered Queue
|
|
---------------
|
|
|
|
The `clustered-queue` example demonstrates a JMS queue deployed on two
|
|
different nodes. The two nodes are configured to form a cluster. We then
|
|
create a consumer for the queue on each node, and we create a producer
|
|
on only one of the nodes. We then send some messages via the producer,
|
|
and we verify that both consumers receive the sent messages in a
|
|
round-robin fashion.
|
|
|
|
Clustering with JGroups
|
|
-----------------------
|
|
|
|
The `clustered-jgroups` example demonstrates how to form a two node
|
|
cluster using JGroups as its underlying topology discovery technique,
|
|
rather than the default UDP broadcasting. We then create a consumer for
|
|
the queue on each node, and we create a producer on only one of the
|
|
nodes. We then send some messages via the producer, and we verify that
|
|
both consumers receive the sent messages in a round-robin fashion.
|
|
|
|
Clustered Standalone
|
|
--------------------
|
|
|
|
The `clustered-standalone` example demonstrates how to configure and
|
|
starts 3 cluster nodes on the same machine to form a cluster. A
|
|
subscriber for a JMS topic is created on each node, and we create a
|
|
producer on only one of the nodes. We then send some messages via the
|
|
producer, and we verify that the 3 subscribers receive all the sent
|
|
messages.
|
|
|
|
Clustered Static Discovery
|
|
--------------------------
|
|
|
|
This example demonstrates how to configure a cluster using a list of
|
|
connectors rather than UDP for discovery
|
|
|
|
Clustered Static Cluster One Way
|
|
--------------------------------
|
|
|
|
This example demonstrates how to set up a cluster where cluster
|
|
connections are one way, i.e. server A -\> Server B -\> Server C
|
|
|
|
Clustered Topic
|
|
---------------
|
|
|
|
The `clustered-topic` example demonstrates a JMS topic deployed on two
|
|
different nodes. The two nodes are configured to form a cluster. We then
|
|
create a subscriber on the topic on each node, and we create a producer
|
|
on only one of the nodes. We then send some messages via the producer,
|
|
and we verify that both subscribers receive all the sent messages.
|
|
|
|
Message Consumer Rate Limiting
|
|
------------------------------
|
|
|
|
With Apache ActiveMQ Artemis you can specify a maximum consume rate at which a JMS
|
|
MessageConsumer will consume messages. This can be specified when
|
|
creating or deploying the connection factory.
|
|
|
|
If this value is specified then Apache ActiveMQ Artemis will ensure that messages are
|
|
never consumed at a rate higher than the specified rate. This is a form
|
|
of consumer throttling.
|
|
|
|
Dead Letter
|
|
-----------
|
|
|
|
The `dead-letter` example shows you how to define and deal with dead
|
|
letter messages. Messages can be delivered unsuccessfully (e.g. if the
|
|
transacted session used to consume them is rolled back).
|
|
|
|
Such a message goes back to the JMS destination ready to be redelivered.
|
|
However, this means it is possible for a message to be delivered again
|
|
and again without any success and remain in the destination, clogging
|
|
the system.
|
|
|
|
To prevent this, messaging systems define dead letter messages: after a
|
|
specified unsuccessful delivery attempts, the message is removed from
|
|
the destination and put instead in a dead letter destination where they
|
|
can be consumed for further investigation.
|
|
|
|
Delayed Redelivery
|
|
------------------
|
|
|
|
The `delayed-redelivery` example demonstrates how Apache ActiveMQ Artemis can be
|
|
configured to provide a delayed redelivery in the case a message needs
|
|
to be redelivered.
|
|
|
|
Delaying redelivery can often be useful in the case that clients
|
|
regularly fail or roll-back. Without a delayed redelivery, the system
|
|
can get into a "thrashing" state, with delivery being attempted, the
|
|
client rolling back, and delivery being re-attempted in quick
|
|
succession, using up valuable CPU and network resources.
|
|
|
|
Divert
|
|
------
|
|
|
|
Apache ActiveMQ Artemis diverts allow messages to be transparently "diverted" or copied
|
|
from one address to another with just some simple configuration defined
|
|
on the server side.
|
|
|
|
Durable Subscription
|
|
--------------------
|
|
|
|
The `durable-subscription` example shows you how to use a durable
|
|
subscription with Apache ActiveMQ Artemis. Durable subscriptions are a standard part of
|
|
JMS, please consult the JMS 1.1 specification for full details.
|
|
|
|
Unlike non-durable subscriptions, the key function of durable
|
|
subscriptions is that the messages contained in them persist longer than
|
|
the lifetime of the subscriber - i.e. they will accumulate messages sent
|
|
to the topic even if there is no active subscriber on them. They will
|
|
also survive server restarts or crashes. Note that for the messages to
|
|
be persisted, the messages sent to them must be marked as durable
|
|
messages.
|
|
|
|
Embedded
|
|
--------
|
|
|
|
The `embedded` example shows how to embed JMS within your own code using
|
|
POJO instantiation and no config files.
|
|
|
|
Embedded Simple
|
|
---------------
|
|
|
|
The `embedded` example shows how to embed JMS within your own code using
|
|
regular Apache ActiveMQ Artemis XML files.
|
|
|
|
Message Expiration
|
|
------------------
|
|
|
|
The `expiry` example shows you how to define and deal with message
|
|
expiration. Messages can be retained in the messaging system for a
|
|
limited period of time before being removed. JMS specification states
|
|
that clients should not receive messages that have been expired (but it
|
|
does not guarantee this will not happen).
|
|
|
|
Apache ActiveMQ Artemis can assign an expiry address to a given queue so that when
|
|
messages are expired, they are removed from the queue and sent to the
|
|
expiry address. These "expired" messages can later be consumed from the
|
|
expiry address for further inspection.
|
|
|
|
Apache ActiveMQ Artemis Resource Adapter example
|
|
---------------------------------
|
|
|
|
This examples shows how to build the activemq resource adapters a rar
|
|
for deployment in other Application Server's
|
|
|
|
HTTP Transport
|
|
--------------
|
|
|
|
The `http-transport` example shows you how to configure Apache ActiveMQ Artemis to use
|
|
the HTTP protocol as its transport layer.
|
|
|
|
Instantiate JMS Objects Directly
|
|
--------------------------------
|
|
|
|
Usually, JMS Objects such as `ConnectionFactory`, `Queue` and `Topic`
|
|
instances are looked up from JNDI before being used by the client code.
|
|
This objects are called "administered objects" in JMS terminology.
|
|
|
|
However, in some cases a JNDI server may not be available or desired. To
|
|
come to the rescue Apache ActiveMQ Artemis also supports the direct instantiation of
|
|
these administered objects on the client side so you don't have to use
|
|
JNDI for JMS.
|
|
|
|
Interceptor
|
|
-----------
|
|
|
|
Apache ActiveMQ Artemis allows an application to use an interceptor to hook into the
|
|
messaging system. Interceptors allow you to handle various message
|
|
events in Apache ActiveMQ Artemis.
|
|
|
|
JAAS
|
|
----
|
|
|
|
The `jaas` example shows you how to configure Apache ActiveMQ Artemis to use JAAS for
|
|
security. Apache ActiveMQ Artemis can leverage JAAS to delegate user authentication and
|
|
authorization to existing security infrastructure.
|
|
|
|
JMS Auto Closable
|
|
-----------------
|
|
|
|
The `jms-auto-closeable` example shows how JMS resources, such as
|
|
connections, sessions and consumers, in JMS 2 can be automatically
|
|
closed on error.
|
|
|
|
JMS Completion Listener
|
|
-----------------------
|
|
|
|
The `jms-completion-listener` example shows how to send a message
|
|
asynchronously to Apache ActiveMQ Artemis and use a CompletionListener to be notified
|
|
of the Broker receiving it.
|
|
|
|
JMS Bridge
|
|
----------
|
|
|
|
The `jms-brige` example shows how to setup a bridge between two
|
|
standalone Apache ActiveMQ Artemis servers.
|
|
|
|
JMS Context
|
|
-----------
|
|
|
|
The `jms-context` example shows how to send and receive a message to a
|
|
JMS Queue using Apache ActiveMQ Artemis by using a JMS Context.
|
|
|
|
A JMSContext is part of JMS 2.0 and combines the JMS Connection and
|
|
Session Objects into a simple Interface.
|
|
|
|
JMS Shared Consumer
|
|
-------------------
|
|
|
|
The `jms-shared-consumer` example shows you how can use shared consumers
|
|
to share a subscription on a topic. In JMS 1.1 this was not allowed and
|
|
so caused a scalability issue. In JMS 2 this restriction has been lifted
|
|
so you can share the load across different threads and connections.
|
|
|
|
JMX Management
|
|
--------------
|
|
|
|
The `jmx` example shows how to manage Apache ActiveMQ Artemis using JMX.
|
|
|
|
Large Message
|
|
-------------
|
|
|
|
The `large-message` example shows you how to send and receive very large
|
|
messages with Apache ActiveMQ Artemis. Apache ActiveMQ Artemis supports the sending and receiving of
|
|
huge messages, much larger than can fit in available RAM on the client
|
|
or server. Effectively the only limit to message size is the amount of
|
|
disk space you have on the server.
|
|
|
|
Large messages are persisted on the server so they can survive a server
|
|
restart. In other words Apache ActiveMQ Artemis doesn't just do a simple socket stream
|
|
from the sender to the consumer.
|
|
|
|
Last-Value Queue
|
|
----------------
|
|
|
|
The `last-value-queue` example shows you how to define and deal with
|
|
last-value queues. Last-value queues are special queues which discard
|
|
any messages when a newer message with the same value for a well-defined
|
|
last-value property is put in the queue. In other words, a last-value
|
|
queue only retains the last value.
|
|
|
|
A typical example for last-value queue is for stock prices, where you
|
|
are only interested by the latest price for a particular stock.
|
|
|
|
Management
|
|
----------
|
|
|
|
The `management` example shows how to manage Apache ActiveMQ Artemis using JMS Messages
|
|
to invoke management operations on the server.
|
|
|
|
Management Notification
|
|
-----------------------
|
|
|
|
The `management-notification` example shows how to receive management
|
|
notifications from Apache ActiveMQ Artemis using JMS messages. Apache ActiveMQ Artemis servers emit
|
|
management notifications when events of interest occur (consumers are
|
|
created or closed, addresses are created or deleted, security
|
|
authentication fails, etc.).
|
|
|
|
Message Counter
|
|
---------------
|
|
|
|
The `message-counters` example shows you how to use message counters to
|
|
obtain message information for a JMS queue.
|
|
|
|
Message Group
|
|
-------------
|
|
|
|
The `message-group` example shows you how to configure and use message
|
|
groups with Apache ActiveMQ Artemis. Message groups allow you to pin messages so they
|
|
are only consumed by a single consumer. Message groups are sets of
|
|
messages that has the following characteristics:
|
|
|
|
- Messages in a message group share the same group id, i.e. they have
|
|
same JMSXGroupID string property values
|
|
|
|
- The consumer that receives the first message of a group will receive
|
|
all the messages that belongs to the group
|
|
|
|
Message Group
|
|
-------------
|
|
|
|
The `message-group2` example shows you how to configure and use message
|
|
groups with Apache ActiveMQ Artemis via a connection factory.
|
|
|
|
Message Priority
|
|
----------------
|
|
|
|
Message Priority can be used to influence the delivery order for
|
|
messages.
|
|
|
|
It can be retrieved by the message's standard header field 'JMSPriority'
|
|
as defined in JMS specification version 1.1.
|
|
|
|
The value is of type integer, ranging from 0 (the lowest) to 9 (the
|
|
highest). When messages are being delivered, their priorities will
|
|
effect their order of delivery. Messages of higher priorities will
|
|
likely be delivered before those of lower priorities.
|
|
|
|
Messages of equal priorities are delivered in the natural order of their
|
|
arrival at their destinations. Please consult the JMS 1.1 specification
|
|
for full details.
|
|
|
|
Multiple Failover
|
|
-----------------
|
|
|
|
This example demonstrates how to set up a live server with multiple
|
|
backups
|
|
|
|
Multiple Failover Failback
|
|
--------------------------
|
|
|
|
This example demonstrates how to set up a live server with multiple
|
|
backups but forcing failover back to the original live server
|
|
|
|
No Consumer Buffering
|
|
---------------------
|
|
|
|
By default, Apache ActiveMQ Artemis consumers buffer messages from the server in a
|
|
client side buffer before you actually receive them on the client side.
|
|
This improves performance since otherwise every time you called
|
|
receive() or had processed the last message in a
|
|
`MessageListener onMessage()` method, the Apache ActiveMQ Artemis client would have to
|
|
go the server to request the next message, which would then get sent to
|
|
the client side, if one was available.
|
|
|
|
This would involve a network round trip for every message and reduce
|
|
performance. Therefore, by default, Apache ActiveMQ Artemis pre-fetches messages into a
|
|
buffer on each consumer.
|
|
|
|
In some case buffering is not desirable, and Apache ActiveMQ Artemis allows it to be
|
|
switched off. This example demonstrates that.
|
|
|
|
Non-Transaction Failover With Server Data Replication
|
|
-----------------------------------------------------
|
|
|
|
The `non-transaction-failover` example demonstrates two servers coupled
|
|
as a live-backup pair for high availability (HA), and a client using a
|
|
*non-transacted* JMS session failing over from live to backup when the
|
|
live server is crashed.
|
|
|
|
Apache ActiveMQ Artemis implements failover of client connections between live and
|
|
backup servers. This is implemented by the replication of state between
|
|
live and backup nodes. When replication is configured and a live node
|
|
crashes, the client connections can carry and continue to send and
|
|
consume messages. When non-transacted sessions are used, once and only
|
|
once message delivery is not guaranteed and it is possible that some
|
|
messages will be lost or delivered twice.
|
|
|
|
OpenWire
|
|
--------
|
|
|
|
The `Openwire` example shows how to configure an Apache ActiveMQ Artemis server to
|
|
communicate with an Apache ActiveMQ Artemis JMS client that uses open-wire protocol.
|
|
|
|
You will find the queue example for open wire, and the chat example.
|
|
|
|
Paging
|
|
------
|
|
|
|
The `paging` example shows how Apache ActiveMQ Artemis can support huge queues even
|
|
when the server is running in limited RAM. It does this by transparently
|
|
*paging* messages to disk, and *depaging* them when they are required.
|
|
|
|
Pre-Acknowledge
|
|
---------------
|
|
|
|
Standard JMS supports three acknowledgement modes:`
|
|
AUTO_ACKNOWLEDGE`, `CLIENT_ACKNOWLEDGE`, and
|
|
`DUPS_OK_ACKNOWLEDGE`. For a full description on these modes please
|
|
consult the JMS specification, or any JMS tutorial.
|
|
|
|
All of these standard modes involve sending acknowledgements from the
|
|
client to the server. However in some cases, you really don't mind
|
|
losing messages in event of failure, so it would make sense to
|
|
acknowledge the message on the server before delivering it to the
|
|
client. This example demonstrates how Apache ActiveMQ Artemis allows this with an extra
|
|
acknowledgement mode.
|
|
|
|
Message Producer Rate Limiting
|
|
------------------------------
|
|
|
|
The `producer-rte-limit` example demonstrates how, with Apache ActiveMQ Artemis, you
|
|
can specify a maximum send rate at which a JMS message producer will
|
|
send messages.
|
|
|
|
Proton Qpid
|
|
-----------
|
|
|
|
Apache ActiveMQ Artemis can be configured to accept requests from any AMQP client that
|
|
supports the 1.0 version of the protocol. This `proton-j` example shows
|
|
a simply qpid java 1.0 client example.
|
|
|
|
Proton Ruby
|
|
-----------
|
|
|
|
Apache ActiveMQ Artemis can be configured to accept requests from any AMQP client that
|
|
supports the 1.0 version of the protocol. This example shows a simply
|
|
proton ruby client that sends and receives messages
|
|
|
|
Queue
|
|
-----
|
|
|
|
A simple example demonstrating a JMS queue.
|
|
|
|
Message Redistribution
|
|
----------------------
|
|
|
|
The `queue-message-redistribution` example demonstrates message
|
|
redistribution between queues with the same name deployed in different
|
|
nodes of a cluster.
|
|
|
|
Queue Requestor
|
|
---------------
|
|
|
|
A simple example demonstrating a JMS queue requestor.
|
|
|
|
Queue with Message Selector
|
|
---------------------------
|
|
|
|
The `queue-selector` example shows you how to selectively consume
|
|
messages using message selectors with queue consumers.
|
|
|
|
Reattach Node example
|
|
---------------------
|
|
|
|
The `Reattach Node` example shows how a client can try to reconnect to
|
|
the same server instead of failing the connection immediately and
|
|
notifying any user ExceptionListener objects. Apache ActiveMQ Artemis can be configured
|
|
to automatically retry the connection, and reattach to the server when
|
|
it becomes available again across the network.
|
|
|
|
Replicated Failback example
|
|
---------------------------
|
|
|
|
An example showing how failback works when using replication, In this
|
|
example a live server will replicate all its Journal to a backup server
|
|
as it updates it. When the live server crashes the backup takes over
|
|
from the live server and the client reconnects and carries on from where
|
|
it left off.
|
|
|
|
Replicated Failback static example
|
|
----------------------------------
|
|
|
|
An example showing how failback works when using replication, but this
|
|
time with static connectors
|
|
|
|
Replicated multiple failover example
|
|
------------------------------------
|
|
|
|
An example showing how to configure multiple backups when using
|
|
replication
|
|
|
|
Replicated Failover transaction example
|
|
---------------------------------------
|
|
|
|
An example showing how failover works with a transaction when using
|
|
replication
|
|
|
|
Request-Reply example
|
|
---------------------
|
|
|
|
A simple example showing the JMS request-response pattern.
|
|
|
|
Rest example
|
|
------------
|
|
|
|
An example showing how to use the Apache ActiveMQ Artemis Rest API
|
|
|
|
Scheduled Message
|
|
-----------------
|
|
|
|
The `scheduled-message` example shows you how to send a scheduled
|
|
message to a JMS Queue with Apache ActiveMQ Artemis. Scheduled messages won't get
|
|
delivered until a specified time in the future.
|
|
|
|
Security
|
|
--------
|
|
|
|
The `security` example shows you how configure and use role based queue
|
|
security with Apache ActiveMQ Artemis.
|
|
|
|
Send Acknowledgements
|
|
---------------------
|
|
|
|
The `send-acknowledgements` example shows you how to use Apache ActiveMQ Artemis's
|
|
advanced *asynchronous send acknowledgements* feature to obtain
|
|
acknowledgement from the server that sends have been received and
|
|
processed in a separate stream to the sent messages.
|
|
|
|
Spring Integration
|
|
------------------
|
|
|
|
This example shows how to use embedded JMS using Apache ActiveMQ Artemis's Spring
|
|
integration.
|
|
|
|
SSL Transport
|
|
-------------
|
|
|
|
The `ssl-enabled` shows you how to configure SSL with Apache ActiveMQ Artemis to send
|
|
and receive message.
|
|
|
|
Static Message Selector
|
|
-----------------------
|
|
|
|
The `static-selector` example shows you how to configure an Apache ActiveMQ Artemis core
|
|
queue with static message selectors (filters).
|
|
|
|
Static Message Selector Using JMS
|
|
---------------------------------
|
|
|
|
The `static-selector-jms` example shows you how to configure an Apache ActiveMQ Artemis
|
|
queue with static message selectors (filters) using JMS.
|
|
|
|
Stomp
|
|
-----
|
|
|
|
The `stomp` example shows you how to configure an Apache ActiveMQ Artemis server to send
|
|
and receive Stomp messages.
|
|
|
|
Stomp1.1
|
|
--------
|
|
|
|
The `stomp` example shows you how to configure an Apache ActiveMQ Artemis server to send
|
|
and receive Stomp messages via a Stomp 1.1 connection.
|
|
|
|
Stomp1.2
|
|
--------
|
|
|
|
The `stomp` example shows you how to configure an Apache ActiveMQ Artemis server to send
|
|
and receive Stomp messages via a Stomp 1.2 connection.
|
|
|
|
Stomp Over Web Sockets
|
|
----------------------
|
|
|
|
The `stomp-websockets` example shows you how to configure an Apache ActiveMQ Artemis
|
|
server to send and receive Stomp messages directly from Web browsers
|
|
(provided they support Web Sockets).
|
|
|
|
Symmetric Cluster
|
|
-----------------
|
|
|
|
The `symmetric-cluster` example demonstrates a symmetric cluster set-up
|
|
with Apache ActiveMQ Artemis.
|
|
|
|
Apache ActiveMQ Artemis has extremely flexible clustering which allows you to set-up
|
|
servers in many different topologies. The most common topology that
|
|
you'll perhaps be familiar with if you are used to application server
|
|
clustering is a symmetric cluster.
|
|
|
|
With a symmetric cluster, the cluster is homogeneous, i.e. each node is
|
|
configured the same as every other node, and every node is connected to
|
|
every other node in the cluster.
|
|
|
|
Temporary Queue
|
|
---------------
|
|
|
|
A simple example demonstrating how to use a JMS temporary queue.
|
|
|
|
Topic
|
|
-----
|
|
|
|
A simple example demonstrating a JMS topic.
|
|
|
|
Topic Hierarchy
|
|
---------------
|
|
|
|
Apache ActiveMQ Artemis supports topic hierarchies. With a topic hierarchy you can
|
|
register a subscriber with a wild-card and that subscriber will receive
|
|
any messages sent to an address that matches the wild card.
|
|
|
|
Topic Selector 1
|
|
----------------
|
|
|
|
The `topic-selector-example1` example shows you how to send message to a
|
|
JMS Topic, and subscribe them using selectors with Apache ActiveMQ Artemis.
|
|
|
|
Topic Selector 2
|
|
----------------
|
|
|
|
The `topic-selector-example2` example shows you how to selectively
|
|
consume messages using message selectors with topic consumers.
|
|
|
|
Transaction Failover
|
|
--------------------
|
|
|
|
The `transaction-failover` example demonstrates two servers coupled as a
|
|
live-backup pair for high availability (HA), and a client using a
|
|
transacted JMS session failing over from live to backup when the live
|
|
server is crashed.
|
|
|
|
Apache ActiveMQ Artemis implements failover of client connections between live and
|
|
backup servers. This is implemented by the sharing of a journal between
|
|
the servers. When a live node crashes, the client connections can carry
|
|
and continue to send and consume messages. When transacted sessions are
|
|
used, once and only once message delivery is guaranteed.
|
|
|
|
Failover Without Transactions
|
|
-----------------------------
|
|
|
|
The `stop-server-failover` example demonstrates failover of the JMS
|
|
connection from one node to another when the live server crashes using a
|
|
JMS non-transacted session.
|
|
|
|
Transactional Session
|
|
---------------------
|
|
|
|
The `transactional` example shows you how to use a transactional Session
|
|
with Apache ActiveMQ Artemis.
|
|
|
|
XA Heuristic
|
|
------------
|
|
|
|
The `xa-heuristic` example shows you how to make an XA heuristic
|
|
decision through Apache ActiveMQ Artemis Management Interface. A heuristic decision is
|
|
a unilateral decision to commit or rollback an XA transaction branch
|
|
after it has been prepared.
|
|
|
|
XA Receive
|
|
----------
|
|
|
|
The `xa-receive` example shows you how message receiving behaves in an
|
|
XA transaction in Apache ActiveMQ Artemis.
|
|
|
|
XA Send
|
|
-------
|
|
|
|
The `xa-send` example shows you how message sending behaves in an XA
|
|
transaction in Apache ActiveMQ Artemis.
|
|
Core API Examples
|
|
=================
|
|
|
|
To run a core example, simply `cd` into the appropriate example
|
|
directory and type `ant`
|
|
|
|
Embedded
|
|
--------
|
|
|
|
The `embedded` example shows how to embed the Apache ActiveMQ Artemis server within
|
|
your own code.
|