public LabelStack getConfigLabelsByPosition(int columnPosition,
int rowPosition) {
LabelStack configLabels = super.getConfigLabelsByPosition(
columnPosition, rowPosition);
if (this.treeData.getDataAtIndex(getRowIndexByPosition(rowPosition)) instanceof GroupByObject) {
configLabels.addLabelOnTop(GROUP_BY_OBJECT);
configLabels.addLabelOnTop(GROUP_BY_COLUMN_PREFIX + columnPosition);
if (getGroupBySummaryProvider(configLabels) != null) {
configLabels.addLabelOnTop(GROUP_BY_SUMMARY);
configLabels.addLabelOnTop(GROUP_BY_SUMMARY_COLUMN_PREFIX
+ columnPosition);