### Question:
StudyCharTableModel extends AbstractTableModel { public int getColumnCount() { return d_pm.countVisibleCharacteristics() + 1; } StudyCharTableModel(StudyListPresentation pm, PresentationModelFactory pmf); int getColumnCount(); int getRowCount(); Object getValueAt(int rowIndex, int columnIndex); @Override String getColumnName(int columnIndex); @Override Class<?> getColumnClass(int columnIndex);  }### Answer:
@Test public void testGetColumnCount() { assertEquals(StudyCharacteristics.values().size() + 1, d_model.getColumnCount()); d_pm.getCharacteristicVisibleModel(StudyCharacteristics.values().get(0)).setValue(Boolean.FALSE); assertEquals(StudyCharacteristics.values().size(), d_model.getColumnCount()); }