public boolean isValid() {
		for (DialogFilterRow filterRow : filterRows) {
			if (!filterRow.hasValidFilterValue()) {
				return false;
			}
		}
		return true;
	}
Checks if this model represents a valid filter. While editing, some elements of the filter
may be incomplete or invalid and if so, then this method will return false.
@return true if the model represents a valid filter.
Ghidra/Framework/Docking/src/main/java/docking/widgets/table/constraint/dialog/ColumnFilterDialogModel.java