If you encounter the following error while running your Mule application, it's because it's looking for activemq supporting classes in your project and it is not finding any.
Those classes are available in activemq-all-x.xx.xx.jar file. Only add activemq-all-x.xx.jar file if your flow is very simple. Otherwise, you may want to check whatever relevant JAR files have to be added as a dependency to your project.
That is available in the root folder where you have unzipped the activemq ZIP file.
The message looks like this:
+ Failed to deploy artifact 'activemqpublisher', see below + ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ org.mule.module.launcher.DeploymentStartException: ClassNotFoundException: org.apache.activemq.ActiveMQConnectionFactory at org.mule.module.launcher.application.DefaultMuleApplication.start(DefaultMuleApplication.java:164) ~[mule-module-launcher-3.8.0.jar:3.8.0] at org.mule.module.launcher.artifact.ArtifactWrapper$4.execute(ArtifactWrapper.java:105) ~[mule-module-launcher-3.8.0.jar:3.8.0]
The reason should be one of the following based on how you have built the application:
If your application is mavenized, then go to POM file and add the following dependency
If your application is not Maven-ized, then right click on your project and click on Properties. In the properties window, select Java Build Path, select the tab Libraries, and click on the button Add external JARS. Select file activemq-all-x.xx.x,jar, which will be available in the root folder of the apache-activemq folder.