An issue with editable JFX TableView - user-interface

Question

I have a little issue with an editable TableView. I want to display data from the database and also be able to edit then which saves it back to the DB.
Now, I can edit it. I have an if statement which checks whether the value is blank (empty or white space) and it works properly, the item in DB doesn't get updated if the value is blank.
My issue is that the blank value still gets displayed. If I click to edit it again, it displays the proper value. Here is a picture of the issue.
Here is the method which creats the table in my view class.
private TableView<Teacher> createTable(){
TableView table = new TableView();
table.setEditable(true);
table.setPrefWidth(500);
table.getSelectionModel().setSelectionMode(SelectionMode.MULTIPLE);
nameColumn = new TableColumn<>("Jméno");
surnameColumn = new TableColumn<>("Příjmení");
nickColumn = new TableColumn<>("Nick");
table.getColumns().addAll(nameColumn, surnameColumn, nickColumn);
int columnCount = table.getColumns().size();
double columnSize = Math.floor(table.getPrefWidth() / columnCount);
nameColumn.setPrefWidth(columnSize);
surnameColumn.setPrefWidth(columnSize);
nickColumn.setPrefWidth(columnSize);
nameColumn.setCellValueFactory(new PropertyValueFactory<>("name"));
surnameColumn.setCellValueFactory(new PropertyValueFactory<>("surname"));
nickColumn.setCellValueFactory(new PropertyValueFactory<>("nick"));
List<Teacher> list = new TeacherDao().getAllTeachers();
ObservableList<Teacher> observableList = FXCollections.observableArrayList(list);
table.setItems(observableList);
return table;
}
Here is the part of the controller class to handle the edits.
private void onEditAction(){
view.getNameColumn().setCellFactory(TextFieldTableCell.forTableColumn());
view.getNameColumn().setOnEditCommit(
new EventHandler<TableColumn.CellEditEvent<Teacher, String>>() {
#Override
public void handle(TableColumn.CellEditEvent<Teacher, String> col) {
String newValue = col.getNewValue();
if(!(CheckString.isBlank(newValue))) {
(col.getTableView().getItems().get(
col.getTablePosition().getRow())
).setName(col.getNewValue());
Teacher teacher = view.getTeacherTableView().getSelectionModel().getSelectedItem();
int id = teacher.getUser_id();
new TeacherDao().updateTeacherNick(id, newValue);
}
}
}
);
view.getSurnameColumn().setCellFactory(TextFieldTableCell.forTableColumn());
view.getSurnameColumn().setOnEditCommit(
new EventHandler<TableColumn.CellEditEvent<Teacher, String>>() {
#Override
public void handle(TableColumn.CellEditEvent<Teacher, String> col) {
String newValue = col.getNewValue();
if(!(CheckString.isBlank(newValue))) {
(col.getTableView().getItems().get(
col.getTablePosition().getRow())
).setName(col.getNewValue());
Teacher teacher = view.getTeacherTableView().getSelectionModel().getSelectedItem();
int id = teacher.getUser_id();
new TeacherDao().updateTeacherNick(id, newValue);
}
}
}
);
view.getNickColumn().setCellFactory(TextFieldTableCell.forTableColumn());
view.getNickColumn().setOnEditCommit(
new EventHandler<TableColumn.CellEditEvent<Teacher, String>>() {
#Override
public void handle(TableColumn.CellEditEvent<Teacher, String> col) {
String newValue = col.getNewValue();
if(!(CheckString.isBlank(newValue))) {
(col.getTableView().getItems().get(
col.getTablePosition().getRow())
).setName(col.getNewValue());
Teacher teacher = view.getTeacherTableView().getSelectionModel().getSelectedItem();
int id = teacher.getUser_id();
new TeacherDao().updateTeacherNick(id, newValue);
}
}
}
);
}
I also tried adding, it didn't help though.
else
(col.getTableView().getItems().get(
col.getTablePosition().getRow())
).setName(col.getOldValue());

Answer 1

Well, I managed to solve it, here is how if anyone is curious
public class TeacherTableView extends TableView {
private TableColumn<Teacher, String> nameColumn, surnameColumn, nickColumn;
TeacherTableView() {
createTable();
onEditAction();
}
private void createTable(){
setEditable(true);
setPrefWidth(500);
getSelectionModel().setSelectionMode(SelectionMode.MULTIPLE);
nameColumn = new TableColumn<>("Jméno");
surnameColumn = new TableColumn<>("Příjmení");
nickColumn = new TableColumn<>("Nick");
getColumns().addAll(nameColumn, surnameColumn, nickColumn);
int columnCount = getColumns().size();
double columnSize = Math.floor(getPrefWidth() / columnCount);
nameColumn.setPrefWidth(columnSize);
nameColumn.setCellValueFactory(cdf -> cdf.getValue().nameProperty());
nameColumn.setCellFactory(TextFieldTableCell.forTableColumn());
nameColumn.setEditable(true);
surnameColumn.setPrefWidth(columnSize);
surnameColumn.setCellValueFactory(cdf -> cdf.getValue().surnameProperty());
surnameColumn.setCellFactory(TextFieldTableCell.forTableColumn());
surnameColumn.setEditable(true);
nickColumn.setPrefWidth(columnSize);
nickColumn.setCellValueFactory(cdf -> cdf.getValue().nickProperty());
nickColumn.setCellFactory(TextFieldTableCell.forTableColumn());
nickColumn.setEditable(true);
List<Teacher> list = new TeacherDao().getAllTeachers();
ObservableList<Teacher> observableList = FXCollections.observableArrayList(list);
setItems(observableList);
}
private void onEditAction(){
nameColumn.setOnEditCommit(this::updateCol);
surnameColumn.setOnEditCommit(this::updateCol);
nickColumn.setOnEditCommit(this::updateCol);
}
private void updateCol(TableColumn.CellEditEvent<Teacher, String> col) {
String newValue = col.getNewValue();
if (CheckString.isNotBlank(newValue)) {
(col.getTableView().getItems().get(
col.getTablePosition().getRow())
).setName(col.getNewValue());
Teacher teacher = (Teacher) getSelectionModel().getSelectedItem();
int id = teacher.getUser_id();
new TeacherDao().updateTeacherNick(id, newValue);
} else {
col.getTableView().refresh();
}
}
}