private boolean initAllRegionEngine(final StoreEngineOptions opts, final Store store) {
        Requires.requireNonNull(opts, "opts");
        Requires.requireNonNull(store, "store");
        String baseRaftDataPath = opts.getRaftDataPath();
        if (Strings.isNotBlank(baseRaftDataPath)) {
            try {
                FileUtils.forceMkdir(new File(baseRaftDataPath));
            } catch (final Throwable t) {
                LOG.error("Fail to make dir for raftDataPath: {}.", baseRaftDataPath);
                return false;
            }
        } else {
            baseRaftDataPath = "";
        }
        final Endpoint serverAddress = opts.getServerAddress();
        final List<RegionEngineOptions> rOptsList = opts.getRegionEngineOptionsList();
        final List<Region> regionList = store.getRegions();
        Requires.requireTrue(rOptsList.size() == regionList.size());
        for (int i = 0; i < rOptsList.size(); i++) {
            final RegionEngineOptions rOpts = rOptsList.get(i);
            if (!inConfiguration(rOpts.getServerAddress().toString(), rOpts.getInitialServerList())) {
                continue;
            }
            final Region region = regionList.get(i);
            if (Strings.isBlank(rOpts.getRaftDataPath())) {
                final String childPath = "raft_data_region_" + region.getId() + "_" + serverAddress.getPort();
                rOpts.setRaftDataPath(Paths.get(baseRaftDataPath, childPath).toString());
            }
            Requires.requireNonNull(region.getRegionEpoch(), "regionEpoch");
            final RegionEngine engine = new RegionEngine(region, this);
            if (engine.init(rOpts)) {
                final RegionKVService regionKVService = new DefaultRegionKVService(engine);
                registerRegionKVService(regionKVService);
                this.regionEngineTable.put(region.getId(), engine);
            } else {
                LOG.error("Fail to init [RegionEngine: {}].", region);
                return false;
            }
        }
        return true;
    }
Storage engine, there is only one instance in a node,
containing one or more {@link RegionEngine}.

@author jiachun.fjc
jraft-rheakv/rheakv-core/src/main/java/com/alipay/sofa/jraft/rhea/StoreEngine.java