​Java call out Error Could not initialize class

[#1]

I am using Java Callout policy where i am intending to publish some test message to kafka topic.

I'm getting below error when I launch the proxy url.

Could not initialize class com.yammer.metrics.Metrics","detail":{"errorcode":"Internal Server Error"}}}

I have added all the dependency jar that required for the java call out jars. callout.png. Please refer attached image.

I tried to adding all the dependency jars with my call out jar and tested but still am getting same error.