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.