code: public BlockchainInfo queryBlockchainInfo(Peer peer, User userContext) throws ProposalException, InvalidArgumentException {
  
          return queryBlockchainInfo(Collections.singleton(peer), userContext);
  
      }
docs: query for chain information
  
  @param peer        The peer to send the request to
  @param userContext the user context to use.
  @return a {@link BlockchainInfo} object containing the chain info requested
  @throws InvalidArgumentException
  @throws ProposalException