Sonar-msg-flow plugin execution in 8.4.2 version of Sonarqube gives classdef not found exception

Hello Folks,

Can someone help me in sorting out Sonar-msg-flow plugin execution in 8.4.2 version of Sonarqube ?
I am unable to start sonarqube.bat after placing sonar-msgflow-plugin-1.1.3.jar in the plugin extension folder of sonarqube 8.4.2 version .sonar-msgflow-plugin for IIB is working only for sonarqube 6.7 version. I have pasted below the error description for 8.4.2 version. I did find some one explaining in the sonar community that some of the deprecated class files are removed from sonar-plugin-api jar file and still it is refering to that class file .For ex: Sensor
Your suggestion will be much appreciated.

2021.07.28 11:14:00 INFO web[o.s.s.p.w.MasterServletFilter] Initializing servlet filter org.sonar.server.platform.web.WebServiceFilter@2f8cd5f0 [pattern=UrlPattern{inclusions=[/api/system/migrate_db.*, …], exclusions=[/api/components/update_key, …]}]
2021.07.28 11:14:00 INFO web[o.s.s.a.EmbeddedTomcat] HTTP connector enabled on port 9000
2021.07.28 11:14:02 ERROR web[o.s.s.p.Platform] Background initialization failed. Stopping SonarQube
java.lang.IllegalStateException: Fail to load plugin Msgflow [msgflow]
at org.sonar.server.plugins.ServerExtensionInstaller.installExtensions(
at org.sonar.server.platform.platformlevel.PlatformLevel4.start(
at org.sonar.server.platform.PlatformImpl.start(
at org.sonar.server.platform.PlatformImpl.startLevel34Containers(
at org.sonar.server.platform.PlatformImpl.access$500(
at org.sonar.server.platform.PlatformImpl$1.lambda$doRun$0(
at org.sonar.server.platform.PlatformImpl$AutoStarterRunnable.runIfNotAborted(
at org.sonar.server.platform.PlatformImpl$1.doRun(
at org.sonar.server.platform.PlatformImpl$
at java.base/
Caused by: java.lang.NoClassDefFoundError: org/sonar/api/batch/Sensor


Welcome to the community!

First, your version is past EOL. You should upgrade to either the latest version or the current LTS at your earliest convenience. Your upgrade path is:

8.4.2 → 8.9.1 → 9.0 (last step optional)

Second, that plugin isn’t supported by SonarSource; you should really contact the plugin maintainer with this question.


Thanks Ann for the quick reply.

I am able to set it up in sonarqube 8.4.2 version.As of now our infrastructure has 8.4.2 version installed.We will be upgrading it some time soon.

I added the sonar-msgflow-plugin-1.3.0-RC1.jar in the extension/plug-in directory of sonarqube 8.4.2 which worked perfectly fine and sonarqube is up now.

I am able to scan the message flow now using sonar-scanner.


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