public void enter(MetricReference metricReference){
  Thread threadId=Thread.currentThread();
  enter(threadId,metricReference);
}

public void enter ( MetricReference metricReference ) { Thread threadId = Thread . currentThread ( ) ; enter ( threadId , metricReference ) ; }
enter a traced zone by the name of metricreference for the current thread . this puts the enter timestamp and all lost call calculations will be based on this timestamp
