IOException - could not find class for resource

 FAQ > Errors > Exceptions > IOException - could not find class for resource

If you get an exception looking like this

Reason: : could not find class for resource: META-INF/services/org/apache/activemq/transport/tcp


You are probably using the ActiveMQ source code without using the resources

Quick fix

Try one of these

  • use one of the distribution jars for ActiveMQ
  • use Maven to run your program
  • try adding activemq/src/conf to your classpath


Then it means that the files in META-INF/services could not be found on the classpath. These files are used to support loose coupling on ActiveMQ with the transport protocols (e.g. to avoid a classpath dependency on JXTA) and to allow dynamic protocol enhancement without a change to the core.

So we’re using the META-INF/services files as a way of coupling a protocol used in URL connections to a Java class name.

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