### Question:
SelectionUtils { public static boolean isMultiHeaderColumn(final GridData uiModel) { return isMultiColumn(uiModel.getSelectedHeaderCells()); }  static boolean isMultiSelect(final GridData uiModel); static boolean isMultiRow(final GridData uiModel); static boolean isMultiColumn(final GridData uiModel); static boolean isMultiHeaderColumn(final GridData uiModel);  }### Answer:
@Test public void testIsMultiHeaderColumnZeroSelections() { assertThat(SelectionUtils.isMultiHeaderColumn(uiModel)).isFalse(); }
@Test public void testIsMultiHeaderColumnSingleSelection() { uiModel.selectHeaderCell(0, 0); assertThat(SelectionUtils.isMultiHeaderColumn(uiModel)).isFalse(); }
@Test public void testIsMultiHeaderColumnMultipleSelections() { uiModel.selectHeaderCell(0, 0); uiModel.selectHeaderCell(0, 1); assertThat(SelectionUtils.isMultiHeaderColumn(uiModel)).isTrue(); }