public void setAgentHistogramMap(List<ResponseTime> responseTimeList) {
            Objects.requireNonNull(responseTimeList, "responseTimeList");
            this.agentHistogramMap = createAgentLevelResponseTime(responseTimeList);
        }
this class is a collection of
applicationHistogram
agentHistogram
applicationTimeHistogram
agentTimeHistogram

@author emeroad
web/src/main/java/com/navercorp/pinpoint/web/applicationmap/histogram/NodeHistogram.java