Integer getStatusCodeFromResponse(Object result) {
        if (result instanceof HttpResponse) {
            HttpResponse response = (HttpResponse) result;

            final StatusLine statusLine = response.getStatusLine();
            if (statusLine != null) {
                return statusLine.getStatusCode();
            } else {
                return null;
            }
        }
        return null;
    }
@author minwoo.jung
@author jaehong.kim
agent-module/plugins/httpclient4/src/main/java/com/navercorp/pinpoint/plugin/httpclient4/interceptor/HttpRequestExecutorExecuteMethodInterceptor.java