Differences and relationship between yammer & codahale & dropwizard Metrics?

Question

Metrics can measure some useful fields, but what's the differences and relations?

Answer 1

It's all the same, but Dropwizard Metrics is the current library name

Coda Hale Yammer Inc.

http://metrics.dropwizard.io

Another thing to look at is that the Maven dependencies for codahale metrics are latest in 2014 and Dropwizard are updated recently