I am new to MDB, so my questions may sound simple.
I implemented an MDB( serving as a Consumer ) using JDeveloper 11.1.7 and built a JAR file using deployment functionality. Now I need to deploy it to WebLogic 10.3 app server. I have several questions:
1) Should I deploy it as a library or as an application?
2) After I successfully deploy and it's in the "RUNNING" mode I assume it should be listening to the particular Queue I specified as a Resource in my MDB implementation. Is that correct?
3) When implementing an MDB all the examples only specify the "destination" but not the "ConnectionFactory". How does it know where to connect to?
Should I deploy it as a library or as an application?
Deploy as an application since the MDB will likely contain business logic specific to the app.
After I successfully deploy and it's in the "RUNNING" mode I assume it
should be listening to the particular Queue I specified as a Resource
in my MDB implementation. Is that correct?
Yes, if your JMS provider is local, specify the name bound in the local JNDI tree for the destination using destination-jndi-name.
When implementing an MDB all the examples only specify the
"destination" but not the "ConnectionFactory". How does it know where
to connect to?
If the MDB is consuming messages from the local WebLogic JMS provider, the container manages configuration for the connections and sessions automatically, so don't set provider-url, initial-context-factory, or connection-factory-jndi-name, unless you have a custom factory to use.
Refer to WebLogic 10.3 documentation for details:
Related
We have noticed our web application is not being deployed on Payara 4.1 when Message Driven Beans fail to connect to the server properly or the queues are missing. We'd rather have the application up and running, then fail a deployment due to JMS connection issues. Is there a way on Payara to prevent deployment crashes due to JMS failing?
EDIT: We use IBM MQ with the wmq.jmsra resource adapter.
You didn't state which exact version of Payara (e.g. 4.1.174) and I forgot when this was added, but could you please try to set the system property
-Ddeployment.resource.validation=false
and check if this behaves as you desire.
You can do
asadmin create-jvm-options -Ddeployment.resource.validation=false
or simply put it in your domain.xml.
We are designing a solution that will consume messages from IBM MQ using JMS. The plan is to use WAS Liberty, so JMS is the technology of choice. We will create Message-Drive beans that will listen for messages in MQ queues.
We are considering both WAS Liberty and OpenLiberty as well.
The trick here is that we must implement it with fail-over, so that if one of our server fail, the other will keep consuming messages from MQ automatically. Like in a ative/passive mechanism.
I'm aware that the MQ adapter needs to be installed as it is not provided out-of-the-box.
I have the following questions:
Does WAS Liberty messaging implementation supports fail-over? Meaning that if the ative message consumer node fails, the stand-by node will automatically migrate and start consuming messages from MQ? What about OpenLiberty?
How can I configure the message system to work that way? Can you point out to the documentation?
Or is this feature only provided by WebSphere?
There is no such functionality in WebSphere Liberty or Open Liberty yet. You can create RFE here https://www.ibm.com/developerworks/rfe/?PROD_ID=544 .
There are ways to do it manually, check these links:
JMS Activation spec on Liberty: “WAS_EndpointInitialState” full profile equivalent property?
Controlling the state of endpoints at runtime
Solution that you could do:
create a script/application that will monitor your servers and call that API to enable/disable endpoint in specific server
or use Dynamic cluster/ auto scaling feature of Liberty and divide you app to two clusters - one with MDBs, one without. And then define policy that MDBs cluster has 1 instance always available. So once the server dies it is automatically restarted somewhere in the cluster
or use Kubernetes/ICP platform in the same way - so deploying 2 versions of app, and defining different replicasets parameters.
We have a requirement for one standalone Java application that can push JMS message to a JMS queue configured on Weblogic, Websphere and JBoss application server.
Is there any generic JMS client library available, that we can use in our application for pushing the messages to any or all of these servers?
As we understand, there is a specific JMS client for each server (for e.g. wljmsclient.jar required for Weblogic target server, as we would need weblogic.jndi.WLInitialContextFactory to be available as Initial Context factory class, similarly for Websphere and JBoss). And we would like to avoid having 3 different JMS client libraries (1 each for server) in the same application.
However, the catch here is, destination server is not known during compilation time. Only during runtime, it will be known whether the given message is to be pushed to Weblogic, Websphere or JBoss server or all of them. Hence, there is a need for a deployed application to support all 3 servers during runtime.
Is there any alternative generic JMS client library?
You can develop your own client that supports the 3 servers.
Basically you need to have for your standalone application :
The different JMS provider jar on the classpath
For example a jms_config.properties file which stores the configuration for each server (initial context factory, etc.)
Then from a generic code you can build the InitialContext, JMS Queues, etc. depending on the target server.
I am developing a service for JMS messaging using IBM WMQ version 7.5 as Message oriented middleware. I am in a dilemma. The IBM specification says to use WebSphere MQ JMS API in JAVA EE environment. My sender and receivers will be in remote JBoss deployments. IBM provides a resource adapter to connect via JCA. This connection requires static administration of components such as Queue managers, queue channels, queue names.
Is JCA the best I can do ? Is there any other way where I can dynamically create the queues provided that I know other configuration details ? There will be multiple applications using this setup running on their own servers. If I use JCA, all have to make their own configurations. Can I make dynamic configurations ?
Typically within the application server environment resources would be created in some JNDI context. These would be Connection Factories and Destinations.
Depending on the app server, it may be possible to share this configuration across a network of individual servers. So typically there would be some set of static definitions.
However within say a servlet the MQConnectionFactory can be dynamically created.
In all cases the backing WMQ Resources do need to exist; though it is possible to send administrative command messages to WMQ to create queues and do other admin. The only exception is topics, accessing a topic string brings it into existence. Though this has default security properties that you might not want.
My j2EE app is currently running on ServiceMix. Now i want to add JMS to my app. The application should able to send/receive the JMS message to/from the queue that stays on MQSeries.
mq.hostname=10.3.6.19
mq.channel=CHANNEL
mq.queueManager=QManager
mq.port=1422
What i would like to do is:
1. Create a jndi.xml file and do configuration for jms stuff.
2. my app will initialize the context, look up jndi name, and create a connection, queueManager, queue. .etc
3. Develop send and receive methods.
My question is:
Can you tell me how to do 1st and 2nd steps.
(the script inside ServiceMix's jndi is diffrent with tomcat's
jndi and others.
ServiceMix using Spring based JNDI provider.
http://servicemix.apache.org/jndi-configuration.html)
I just ran into something similar with Weblogic. The following link uses spring-dm to integrate with websphere. It also takes it to the next logical step and adds camel to the mix.
http://lowry-techie.blogspot.com/2010/11/camel-integration-with-websphere-mq.html
Without using Spring-dm, you may run into classloader issues when trying to load the InitialContextFactory from the websphere jar (this is an issue I had with the Weblogic jar)