code: public String[] getPropertiesInTextFilter()
      {
          List<String> filterProperties = new ArrayList<String>(getColumnCount());
          for (PropertyColumn column : columns)
          {
              if (column.isFilterColumn())
                  filterProperties.add(column.getPropertyName());
          }
          return filterProperties.toArray(new String[filterProperties.size()]);
      }
docs: {@inheritDoc}