@Override
	public Collection<ColumnConstraint<?>> getColumnConstraints() {
		List<ColumnConstraint<?>> list = new ArrayList<>();

		// @formatter:off
		list.add(new AtLeastDateColumnConstraint(DEFAULT_DATE, new LocalDateEditorProvider()));
		list.add(new AtMostDateColumnConstraint(DEFAULT_DATE, new LocalDateEditorProvider()));
		list.add(new InDateRangeColumnConstraint(DEFAULT_DATE, DEFAULT_DATE, new LocalDateRangeEditorProvider()));
		list.add(new NotInDateRangeColumnConstraint(DEFAULT_DATE, DEFAULT_DATE, new LocalDateRangeEditorProvider()));

		// @formatter:on

		return list;
	}
Date object representing an invalid date.
Ghidra/Framework/Docking/src/main/java/docking/widgets/table/constraint/provider/DateColumnConstraintProvider.java