Weblogic Thin T3 client

Helidon 2

Javax based Helidon 2.x works well with wlthint3client.jar, you can use it directly or with Helidon messaging JMS connector: https://medium.com/helidon/helidon-messaging-with-weblogic-jms-7e6ecccdd82d

Helidon 3

Since Helidon 3.x and higher is jakartified(dropping javax.* packages and fully-embracing jakarta.* packages), no libraries using older javax based HK2 injection engine work on the same classpath.

This is the case of Weblogic wlthint3client.jar client library, most commonly used for connecting to JMS resources hosted by Weblogic server.

Startup error when javax based wlthint3client.jar is on classpath:

Caused by: java.lang.NoSuchMethodException: The class GlobalServiceLocator has no constructor marked @Inject and no zero argument constructor
	at org.jvnet.hk2.internal.Utilities.findProducerConstructor(Utilities.java:1326)
...
java.lang.IllegalStateException: Could not find an implementation of ClassAnalyzer with name default
        at org.jvnet.hk2.internal.ServiceLocatorImpl.getAnalyzer(ServiceLocatorImpl.java:2468)

While with Helidon 2.x it was possible to use messaging JMS connector with wlthint3client.jar. With Helidon 3.x and newer specialized Weblogic messaging connector is needed:

<dependency>
    <groupId>io.helidon.messaging.wls-jms</groupId>
    <artifactId>helidon-messaging-wls-jms</artifactId>
</dependency>

Weblogic connector isolates the wlthint3client.jar in specialized classloader, keeping it from crashing Helidon's HK2.

mp:
  messaging:
    connector:
      helidon-weblogic-jms:
        # JMS factory configured in Weblogic
        jms-factory: jms/TestConnectionFactory
        # Path to the WLS Thin T3 client jar
        thin-jar: /path/to/wlthint3client.jar
        url: t3://localhost:7001
        principal: jms_user
        credentials: Welcome1
    incoming:
      from-wls:
        connector: helidon-weblogic-jms
        # WebLogic CDI Syntax(CDI stands for Create Destination Identifier)
        destination: ./TestJMSModule!TestQueue
    outgoing:
      to-wls:
        connector: helidon-weblogic-jms
        destination: ./TestJMSModule!TestQueue

⚠️ Avoid placing wlthint3client.jar on Helidon classpath, client library location needs to be configured and loaded by Helidon messaging connector.

⚠️ Don't forget to start your Helidon app with --add-opens=java.base/java.io=ALL-UNNAMED to allow wlthint3client use reflection.

Weblogic destination CDI Syntax

When connecting to Weblogic cluster with Helidon JMS or Weblogic messaging connector, destination property needs to be configured with Weblogic CDI syntax, NOT with JNDI. This is because Weblogic JMS implementation, unlike other JMS clients, expects CDI destination locators instead of JNDI on the JMS session methods (Session.createTopic(String name), Session.createQueue(String name)).

WebLogic CDI(Create Destination Identifier, don't confuse with dependency injection), is Weblogic's custom syntax for locating Queues and Topics over JMS API methods Session.createTopic(String name) and Session.createQueue(String name) with actual MBean names(Name in WLS console).

Non-Distributed Destinations

When accessing non-distributed queue/topic you need to specify:

• JMS server name
• JMS module name
• Queue/Topic name

With following syntax: jms-server-name/jms-module-name!destination-name

When you know that queue or topic you want to access is on the same server as JMS Connection Factory you are using, server affinity is possible with ./ instead of full server name. ./jms-module-name!destination-name

Uniform Distributed Destinations (UDDs)

Distributed queues/topics are logical destinations acting as load balancers between physical queues/topics usually residing on separated JMS servers/cluster nodes(UDD members). When you need to access UDD you can use following syntax on any cluster server, admin or managed one:

jms-module-name!udd-name

⚠️ UDD destination must not contain ./ or /

To directly access an UDD member queue/topic, you need to use syntax for non-distributed destination: jms-server-name/jms-module-name!member-name

Example: TestJmsServer-1/TestJMSModule!TestJmsServer-1@udd_queue