How to use

org.apache.tapestry5.grid.SortConstraint

constructor

public List<SortConstraint> getSortConstraints() {
  if (sortColumnId == null)
    return Collections.emptyList();
  PropertyModel sortModel = getDataModel().getById(sortColumnId);
  SortConstraint constraint = new SortConstraint(sortModel,
      getColumnSort());
  return Collections.singletonList(constraint);
}

public List<SortConstraint> getSortConstraints()
{
  // In a few limited cases we may not have yet hit the SetupRender phase, and the model may be null.
  if (paginationModel == null || paginationModel.getSortColumnId() == null)
  {
    return Collections.emptyList();
  }
  PropertyModel sortModel = getDataModel().getById(paginationModel.getSortColumnId());
  SortConstraint constraint = new SortConstraint(sortModel, getColumnSort());
  return Collections.singletonList(constraint);
}

  private void sort(String propertyName, boolean ascending, int... ids)
  {
    PropertyModel propertyModel = model.get(propertyName);

    int availableRows = source.getAvailableRows();

    SortConstraint constraint = new SortConstraint(propertyModel,
                            ascending ? ColumnSort.ASCENDING : ColumnSort.DESCENDING);
    List<SortConstraint> constraints = Collections.singletonList(constraint);

    source.prepare(0, availableRows - 1, constraints);

    for (int i = 0; i < ids.length; i++)
    {
      Datum row = (Datum) source.getRowValue(i);

      assertEquals(row.getId(), ids[i], "Id for Datum #" + i);
    }
  }
}