Thanks Gwenn.

I found a link for integrating AppDynamics (agent based monitoring like Wily) with PCF, where its mentioned to create user-defined service and bind it to application, so that AppDynamic agent will detect the service 'VCAP_SERVICE' and start sending metrics/logs to AppDynamic collector.
http://blog.pivotal.io/pivotal-cloud-foundry/products/getting-started-with-pivotal-cloud-foundry-and-appdynamics

I am using here they are using 'collector' and not firehose nozzle?
So does that mean I should not be using (java_buildpack agent of introscope) https://github.com/cloudfoundry/java-buildpack/blob/master/docs/framework-introscope_agent.md
where introscope will need VCAP_SERVICE i.e. service binding with substring as 'introscope' to all my java apps ? I think its old 'collector' approach like AppDynamic ?
And I should not be creating in user defined service for Introscope and bind to my java apps?
I should rely on dea and metron to provide java application metrics and configure my firehose nozzle to point to Introscope-Enterprise Manager to collect all App metrics, is it correct? If yes, then are we saying firehouse metric will be auto understood by Introscope-Enterprise Manager?

Thanks for all your response.