public ElasticStreamSlice newSlice(String streamName) throws IOException {
        // seal last slice with the same stream name when create new segment
        ElasticStreamSlice lastSlice = lastSlices.get(streamName);
        if (lastSlice != null) {
            lastSlice.seal();
        }
        Stream stream = streamManager.getStream(streamName);
        ElasticStreamSlice streamSlice = new DefaultElasticStreamSlice(stream, SliceRange.of(Offsets.NOOP_OFFSET, Offsets.NOOP_OFFSET));
        lastSlices.put(streamName, streamSlice);
        return streamSlice;
    }
Elastic log dimension stream segment manager.
core/src/main/scala/kafka/log/streamaspect/ElasticStreamSliceManager.java