 isFirst true if this the first column
     * @param isLast true if this the last column
     */
    private void buildHeader(TableRowBuilder out, Header&lt;?&gt; header, Column&lt;ContactInfo, ?&gt; column,
        Column&lt;?, ?&gt; sortedColumn, boolean isSortAscending, boolean isFirst, boolean isLast) {
      // Choose the classes to include with the element.
      Style style = dataGrid.getResources().style();
      boolean isSorted = (sortedColumn == column);
      StringBuilder classesBuilder = new S