Applications that run in WebSphere Application Server for z/OS can use JRas to provide tracing support that is consistent with WebSphere tracing.
Instrumented applications use the JRas interfaces and classes for logging and tracing; trace data is written to the same component trace data set as the internal traces issued by the WebSphere Application Server for z/OS runtime. So you can gather application trace data in the same locations, and use the same commands to start and stop CTRACE for these JRas applications as you do for WebSphere Application Server for z/OS server in which the applications are running.