@Override
    public String toString() {
        StringBuilder sb = new StringBuilder("ElasticLogMeta{");
        sb.append("streamMap=").append(streamMap).append(", ");

        int size = segmentMetas.size();
        sb.append("segmentMetas.size=").append(size).append(", ");
        if (size > 10) {
            List<ElasticStreamSegmentMeta> firstFiveSegmentMetas = segmentMetas.subList(0, 5);
            List<ElasticStreamSegmentMeta> lastFiveSegmentMetas = segmentMetas.subList(size - 5, size);

            sb.append("segmentMetas=[");
            for (ElasticStreamSegmentMeta meta : firstFiveSegmentMetas) {
                sb.append(meta).append(", ");
            }
            sb.append("..., ");
            for (ElasticStreamSegmentMeta meta : lastFiveSegmentMetas) {
                sb.append(meta).append(", ");
            }
            // remove the last ", "
            sb.setLength(sb.length() - 2);
            sb.append("]");
        } else {
            sb.append("segmentMetas=").append(segmentMetas);
        }

        sb.append('}');
        return sb.toString();
    }
segmentMeta List for this topicPartition. Each segmentMeta refers to a logical Kafka segment(including log, index, time-index, txn).
core/src/main/scala/kafka/log/streamaspect/ElasticLogMeta.java