Is there a way to run ActiveMq offline?
It depends on what you mean by offline.
You can start a broker inside of a Java application simply by creating a ConnectionFactory like so:
ActiveMQConnectionFactory cf = new ActiveMQConnectionFactory("vm://localhost?broker.persistent=false");
This broker would only be accessible from within the Java application where it was created using the vm://localhost transport.
Bruce
Yes, you can do something like "running offline" by embedding broker into JVM. This is usually done for (unit) testing.
BrokerService broker = new BrokerService();
// configure the broker
broker.addConnector("tcp://localhost:61616");
broker.start();
Related
I'm using Apache ActiveMQ Artemis (N1) for my work, and recently I've got a task to send some messages to another ActiveMQ "Classic" (N2) which is used by another system. However, I don't know how should I write divert configurations at broker.xml file. Is it possible? Could you give an example of divert to another URL-address and queue. Where should I write login/password for connection to N2?
Diverts in ActiveMQ Artemis only work with local resources. To send messages to another instance of ActiveMQ Artemis you'd use a core bridge. However, that only works between instances of ActiveMQ Artemis. ActiveMQ "Classic" doesn't support the protocol which the core bridge uses.
In order to send messages from ActiveMQ Artemis to ActiveMQ "Classic" you'd need to use something like Camel or the JMS bridge shipped with ActiveMQ Artemis. Both of these solutions can be deployed as web applications using the embedded web application server in ActiveMQ Artemis. We ship examples of both. The Camel example is in examples/features/standard/camel/ and the JMS bridge example is in examples/submodules/inter-broker-bridge.
I need your help to suggest me how best I can achieve load balancing using the below diagram. here I am trying to create 2 machines with Master and expecting that the consumer/publisher application will use one common URL( a load-balanced one), where I should not expose the individual VM machine info and port ID. just that load balancer should take care of routing..
this is typically what we do with help of F5 load balancer or HTTP load balancer ..just wondering can be achieved over ActiveMQ and its advisable..?
on other side, I also tried configuring this way on weblogic to consume data from ActiveMQ queue
failover://(tcp://localhost:61616,tcp://localhost:61617)?randomize=true but this does not help.. or WebLogic is not understanding this format.
Messaging connections are stateful. They are not stateless like HTTP connections, and therefore cannot be load-balanced in the same way as HTTP connections. It may be possible to configure an F5 to deal with stateful messaging connections, but I can't say for sure. I'm not an expert on F5.
Both the ActiveMQ Artemis broker itself as well as the JMS client shipped with the broker have load-balancing functionality built in. There's too much to cover here so I recommend you review the clustering documentation for the relevant details.
You might also try using the broker balancer feature. It's currently experimental, but it should be ready to use in the 2.21.0 release coming in the March/April time-frame. It can act like an F5 for your messaging connections, but it can do some more intelligent things like always sending certain clients to the same node which can facilitate certain use-cases which are not possible in a traditional cluster.
The URL failover://(tcp://localhost:61616,tcp://localhost:61617)?randomize=true which are you using is for the OpenWire JMS client shipped with ActiveMQ 5.x. If you're using the core JMS client shipped with ActiveMQ Artemis then you should be using a URL like this instead:
(tcp://localhost:61616,tcp://localhost:61617)?ha=true
I need to start a queue in OpenEJB in a "paused" state so no messages are processed by the consumer until some related data is available. I can programmatically pause the queue as shown here, so if there was some initializer function that is called when a queue is created I could use that method. The queue configuration documentation does not seem to support setting the paused state. Any ideas on how to configure the queue upon creation?
If you read the thread you link you will see a queue is not paused but a broker can be.
In TomEE broker is created from a factory using a spi (in tomee classloader so tomee/lib by default) so you can write your own if that's an option starting programmatically when you are ready.
Now I suspect you don't want to start connectors with the container but it is not an issue to start the broker. Said otherwise you don't want to be connected to any other machine through JMS to not receive anything but if JMS is started and deployed it is ok.
In such a case you can just not configure any connector on the broker and add them when ready. You can find brokers doing:
new org.apache.openejb.resource.activemq.ActiveMQ5Factory().getBrokers()
I am working on developing an interface between TomEE application server and rabbitmq.
Is there any example that can show me what is to be configured in the tomEE server ?
How can I initiate tomEE to create a exchange and queue and than send out messages ?
not sure I fully got the question bu you can embed java client in your application and use Java API: http://www.rabbitmq.com/tutorials/tutorial-one-java.html
If you want to use JMS you can rely on https://github.com/imatix/openamq-jms but since there is no rabbitmq resource adapter it is still "manual".
I'm working on a project where I have several war files inside a tomcat 7 have to communicate with a single embedded activeMQ (5.5.1) broker inside the same Tomcat.
I'm wondering what was the best practice to manage this and how to start and stop the broker properly.
Actually I try tu use a global JNDI entry in server.xml and in each war gets my activemq connection with a lookup. The first connection to the broker implicitly starts it. But with this method I run into various problems like instance already existing or locks in data store.
Should I use instead an additional war which uses a BrokerFactory to start the broker explicitly? In this case how to make sure that this war executes first in Tomcat ? And how do I stop my broker and where?
Thanks for the help.
from the docs...
If you are using the VM transport and wish to explicitly configure an
Embedded Broker there is a chance that you could create the JMS
connections first before the broker starts up. Currently ActiveMQ will
auto-create a broker if you use the VM transport and there is not one
already configured. (In 5.2 it is possible to use the waitForStart and
create=false options for the connection uri)
So to work around this if you are using Spring you may wish to use the
depends-on attribute so that your JMS ConnectionFactory depends on the
embedded broker to avoid this happening. e.g.
see these pages for more information...
http://activemq.apache.org/vm-transport-reference.html
http://activemq.apache.org/how-do-i-embed-a-broker-inside-a-connection.html
http://activemq.apache.org/how-do-i-restart-embedded-broker.html