@Override
  public GetCachedFilesListResponse getCachedFilesList(RpcController controller,
    GetCachedFilesListRequest request) throws ServiceException {
    GetCachedFilesListResponse.Builder responseBuilder = GetCachedFilesListResponse.newBuilder();
    List<String> fullyCachedFiles = new ArrayList<>();
    server.getBlockCache().flatMap(BlockCache::getFullyCachedFiles).ifPresent(fcf -> {
      fullyCachedFiles.addAll(fcf.keySet());
    });
    return responseBuilder.addAllCachedFiles(fullyCachedFiles).build();
  }
Scan data in a table.
@param controller the RPC controller
@param request    the scan request
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/RSRpcServices.java