code: @Override
    public OperationHandle getColumns(SessionHandle sessionHandle,
        String catalogName, String schemaName, String tableName, String columnName)
            throws HiveSQLException {
      try {
        TGetColumnsReq req = new TGetColumnsReq();
        req.setSessionHandle(sessionHandle.toTSessionHandle());
        req.setCatalogName(catalogName);
        req.setSchemaName(schemaName);
        req.setTableName(tableName);
        req.setColumnName(columnName);
        TGetColumnsResp resp = cliService.GetColumns(req);
        checkStatus(resp.getStatus());
        TProtocolVersion protocol = sessionHandle.getProtocolVersion();
        return new OperationHandle(resp.getOperationHandle(), protocol);
      } catch (HiveSQLException e) {
        throw e;
      } catch (Exception e) {
        throw new HiveSQLException(e);
      }
    }
docs: /* (non-Javadoc)
  @see org.apache.hive.service.cli.ICLIService#getColumns(org.apache.hive.service.cli.SessionHandle)