@Override
  public CompletableFuture<ClusterMetrics> getClusterMetrics(EnumSet<Option> options) {
    return this.<ClusterMetrics> newMasterCaller()
      .action((controller, stub) -> this.<GetClusterStatusRequest, GetClusterStatusResponse,
        ClusterMetrics> call(controller, stub,
          RequestConverter.buildGetClusterStatusRequest(options),
          (s, c, req, done) -> s.getClusterStatus(c, req, done),
          resp -> ClusterMetricsBuilder.toClusterMetrics(resp.getClusterStatus())))
      .call();
  }
Get the region info for the passed region name. The region name may be a full region name or
encoded region name. If the region does not found, then it'll throw an UnknownRegionException
wrapped by a {@link CompletableFuture}
@return region info, wrapped by a {@link CompletableFuture}
hbase-client/src/main/java/org/apache/hadoop/hbase/client/RawAsyncHBaseAdmin.java