public ArrayList<BusinessObject> getSelectedObjects() {
        int[] rows = getSelectedRows();
        ArrayList<BusinessObject> businessObjectArrayList = new ArrayList<>();
        for(int row : rows) {
            BusinessObject businessObject = (BusinessObject) model.getValueAt(row, 0);
            businessObjectArrayList.add(businessObject);
        }
        // check on which element is clicked
        BusinessObject selectedObject = getSelectedObject();
        if(businessObjectArrayList.contains(selectedObject))
            // return all selected elements if mouse was clicked on one of them
            return businessObjectArrayList;
        else {
            // otherwise return only the clicked element
            ArrayList<BusinessObject> list = new ArrayList<>();
            list.add(selectedObject);
            return list;
        }

    }