public void finish() {
        // snapshot last image
        final Shared shared = traceRoot.getShared();
        if (shared.getStatusCode() != 0) {
            Annotation<Integer> annotation = Annotations.of(AnnotationKey.HTTP_STATUS_CODE.getCode(), shared.getStatusCode());
            this.addAnnotation(annotation);
        }
    }
Span represent RPC

@author netspider
@author emeroad
agent-module/profiler/src/main/java/com/navercorp/pinpoint/profiler/context/Span.java