@Override
  protected void createColumns(
      DefaultCellTable<Transformer> table, ListDataProvider<Transformer> dataProvider) {
    TextColumn<Transformer> fromColumn =
        new TextColumn<Transformer>() {
          @Override
          public String getValue(Transformer transform) {
            return transform.getFrom();
          }
        };
    fromColumn.setSortable(true);

    TextColumn<Transformer> toColumn =
        new TextColumn<Transformer>() {
          @Override
          public String getValue(Transformer transform) {
            return transform.getTo();
          }
        };
    toColumn.setSortable(true);

    TextColumn<Transformer> typeColumn =
        new TextColumn<Transformer>() {
          @Override
          public String getValue(Transformer transform) {
            return transform.getType();
          }
        };
    typeColumn.setSortable(true);

    ColumnSortEvent.ListHandler<Transformer> sortHandler =
        new ColumnSortEvent.ListHandler<Transformer>(dataProvider.getList());
    sortHandler.setComparator(fromColumn, createColumnCommparator(fromColumn));
    sortHandler.setComparator(toColumn, createColumnCommparator(toColumn));
    sortHandler.setComparator(typeColumn, createColumnCommparator(typeColumn));

    table.addColumn(fromColumn, "From");
    table.addColumn(toColumn, "To");
    table.addColumn(typeColumn, "Type");

    table.addColumnSortHandler(sortHandler);
    table.getColumnSortList().push(typeColumn);
    table.getColumnSortList().push(toColumn);
    table.getColumnSortList().push(fromColumn);

    table.setWidth("100%", false);
    table.setColumnWidth(fromColumn, 45, Style.Unit.PCT);
    table.setColumnWidth(toColumn, 45, Style.Unit.PCT);
    table.setColumnWidth(typeColumn, 10, Style.Unit.PCT);
  }
  @SuppressWarnings("unchecked")
  @Override
  protected void createColumns(
      DefaultCellTable<ArtifactReference> table, ListDataProvider<ArtifactReference> dataProvider) {
    final TextColumn<ArtifactReference> nameColumn =
        new TextColumn<ArtifactReference>() {
          @Override
          public String getValue(ArtifactReference reference) {
            return reference.getName();
          }
        };
    nameColumn.setSortable(true);

    final TextColumn<ArtifactReference> urlColumn =
        new TextColumn<ArtifactReference>() {
          @Override
          public String getValue(ArtifactReference reference) {
            return reference.getUrl();
          }
        };
    urlColumn.setSortable(true);

    ColumnSortEvent.ListHandler<ArtifactReference> sortHandler =
        new ColumnSortEvent.ListHandler<ArtifactReference>(dataProvider.getList());
    sortHandler.setComparator(nameColumn, createColumnCommparator(nameColumn));
    sortHandler.setComparator(urlColumn, createColumnCommparator(urlColumn));

    table.addColumn(nameColumn, "Name");
    table.addColumn(urlColumn, "URL");
    table.addColumnSortHandler(sortHandler);

    table.addColumnSortHandler(sortHandler);
    table.getColumnSortList().push(urlColumn);
    table.getColumnSortList().push(nameColumn);
  }