@Override
        protected Bytes getBaseKey(final Bytes indexKey) {
            final byte[] keyBytes = KeyFirstWindowKeySchema.extractStoreKeyBytes(indexKey.get());
            final long timestamp = KeyFirstWindowKeySchema.extractStoreTimestamp(indexKey.get());
            final int seqnum = KeyFirstWindowKeySchema.extractStoreSequence(indexKey.get());
            return TimeFirstWindowKeySchema.toStoreKeyBinary(keyBytes, timestamp, seqnum);
        }
A RocksDB backed time-ordered segmented bytes store for window key schema.
streams/src/main/java/org/apache/kafka/streams/state/internals/RocksDBTimeOrderedWindowSegmentedBytesStore.java