@Override
    public String toString() {
        return "SpanBo{" +
                "version=" + version +
                ", agentId='" + agentId + '\'' +
                ", agentName='" + agentName + '\'' +
                ", applicationName='" + applicationName + '\'' +
                ", agentStartTime=" + agentStartTime +
                ", transactionId=" + transactionId +
                ", spanId=" + spanId +
                ", parentSpanId=" + parentSpanId +
                ", parentApplicationName='" + parentApplicationName + '\'' +
                ", parentApplicationServiceType=" + parentApplicationServiceType +
                ", startTime=" + startTime +
                ", elapsed=" + elapsed +
                ", rpc='" + rpc + '\'' +
                ", serviceType=" + serviceType +
                ", endPoint='" + endPoint + '\'' +
                ", apiId=" + apiId +
                ", annotationBoList=" + annotationBoList +
                ", flag=" + flag +
                ", errCode=" + errCode +
                ", spanEventBoList=" + spanEventBoList +
                ", spanChunkBoList=" + spanChunkBoList +
                ", collectorAcceptTime=" + collectorAcceptTime +
                ", exceptionInfo=" + exceptionInfo +
                ", exceptionClass='" + exceptionClass + '\'' +
                ", applicationServiceType=" + applicationServiceType +
                ", acceptorHost='" + acceptorHost + '\'' +
                ", remoteAddr='" + remoteAddr + '\'' +
                ", loggingTransactionInfo=" + loggingTransactionInfo +
                '}';
    }
@return loggingInfo key
@see com.navercorp.pinpoint.common.trace.LoggingInfo
commons-server/src/main/java/com/navercorp/pinpoint/common/server/bo/SpanBo.java