I am trying to add metrics to a plain Java application using codahale metrics. I\'d like to use the @Timed annotation, but it is unclear to me which MetricRegistry it uses,
As the other answer stated, you have to have something in the application to listen for your instantiated classes and check them for the @Timed annotation.
If you're using Guice, you could use: https://github.com/palominolabs/metrics-guice