code: public String get(final String key, final String columnName) throws HectorException {
      ColumnQuery<String, String, String> q = HFactory.createColumnQuery(keyspace,
          serializer, serializer, serializer);
      QueryResult<HColumn<String, String>> r = q.setKey(key).
          setName(columnName).
          setColumnFamily(columnFamilyName).
          execute();
      HColumn<String, String> c = r.get();
      return c != null ? c.getValue() : null;
    }
docs: Get a string value.
  
  @return The string value; null if no value exists for the given key.