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Java DefaultTableModel- how do I remove the selected row?

I have a table displayed in my Java GUI, which the user can add rows to by clicking an 'Add' button. The cells in the row that is added to the table are all editable by default, and the user can select each row/ cell as they wish.
I now want to add the functionality to remove a row from the table, but I can't seem to find the correct way to do this with a DefaultTableModel data type.
I have added the following code to the action listener for my 'remove row' button:
removeBtn.addActionListener(new ActionListener(){
public void removeRow(){
DefaultTableModel model = (DefaultTableModel)jEntityFilterTable.getModel();
model.removeRow();
}
});
However, the removeRow() method requires a parameter of type int (the index number of the row I want to remove). How can I get the 'selected row' from the DefaultTableModel? There doesn't appear to be a method that allows you to do this...

You can obtain the index from the table.
removeBtn.addActionListener(new ActionListener(){
public void removeRow(){
int selRow = jEntityFilterTable.getSelectedRow();
if(selRow != -1) {
DefaultTableModel model = (DefaultTableModel)jEntityFilterTable.getModel();
model.removeRow(selRow);
}
}
});

Detecting Cell Click On A Table Row That Is Already Selected

I have a JFrame application that contains a JTabel. The underlying table model is my own class that I made that extends AbstractTableModel. The data in the first column is of type boolean and so I want it to show the value in the form of a checkbox. To do this, I added the following code in my table model getColumnClass method:
#Override
public Class<?> getColumnClass(int columnIndex) {
if (columnIndex == 0) {
return Boolean.class;
} else if (columnIndex == 1) {
....
....
}
This works fine and my table cell looks like the following which is what I want:
The behavior I now want is that when the user clicks on a cell in column 0 of any row I want to toggle the value of On Sale.
My main class listens to selections in the table by implementing ListSelectionListener and overriding the valueChanged method. Inside the valueChanged method I can check the selected column by calling table.getSelectedColumn and checking to see if it's 0 then getting the object at the selected row and toggling the boolean on sale value.
The problem I am running into is that if a particular row is already selected and the user clicks the cell in column 0 for the selected row the valueChanged method is never called and so therefore I never toggle the value.
My quesion is, how do I detect a cell selection/click on a row that is already selected? Should I use a mouse selection listener then determine the cell that was clicked using the location data from the mouse click event?
Thank you.

Have you tried listening to table change instead ? You would need to implement TableModelListener and to have this :
public void tableChanged(TableModelEvent e) {
int row = e.getFirstRow();
int column = e.getColumn();
TableModel model = (TableModel)e.getSource();
String columnName = model.getColumnName(column);
Object data = model.getValueAt(row, column);
...// Do something with the data...
}

GWT DataGrid row selection

I have a GWT DataGrid with a multi-selection model and check-boxes to show selection/select/deselect rows. That's all well and good.
But, I also want to have a second, independent selection model. If a user double-clicks on a row, I want to handle that event, and for the event handler to know which row was double-clicked. The double-clicking should not affect the check-box selection.
I tried this:
final SelectionModel<MyRecord> selectionModel = new MultiSelectionModel...
//Yes I need a MultiSelectionModel
dataGrid.addDomHandler(new DoubleClickHandler() {
public void onDoubleClick(DoubleClickEvent event) {
selectionModel.get??? //no suitable getter for double-clicked
}
}, DoubleClickEvent.getType());
But ran into a dead-end when I found now way to get the double-clicked row in the event handler. One way would be to register both a Multi- and Single- selection model, but doubt DataGrid will support that.
Neither can I work out how to get the clicked row from the DoubleClickEvent object.
I have implemented a button cell with a FieldUpdater. This works, but it's not ideal.
Any suggestions?

If I understand correctly you want to get the index of the row.
You could do it like this: (this way you'll get the "Real" index)
AbstractSelectionModel<T> selectionModel = (AbstractSelectionModel<T>)dataGrid.getSelectionModel();
ArrayList<Integer> intList = new ArrayList<Integer>();
List<Row> list = (List<Row>)_dataProvider.getList();
int i = 0;
for(Row row : list)
{
if( selectionModel.isSelected(row) )
intList.add(i);
i++;
}
UPDATE:
To get only the current row you could do that:
datagrid.getKeyboardSelectedRow()

I'm 3 years too late to the party, but I think the more correct solution would be:
dataGrid.addCellPreviewHandler(new CellPreviewEvent.Handler<YOUR_MODEL_TYPE>() {
#Override
public void onCellPreview(final CellPreviewEvent<YOUR_MODEL_TYPE> event) {
if (BrowserEvents.DBLCLICK.equalsIgnoreCase(event.getNativeEvent().getType())) {
int row = event.getIndex();
doStuff(row); // do whatever you need the row index for
}
}
});

Excel-like JTable Cell Editor, with an empty cell at edition start

I'm trying to have a JTable edition working like in excel: if I start editing a cell, the cell becomes empty for receiving the new entry. The goal is to avoid the user having to delete the existing cell content first.
I can already detect cell start/stop edition by adding a PropertyChangeListener working as follow:
public void propertyChange(PropertyChangeEvent e)
{
// A cell has started/stopped editing
if ("tableCellEditor".equals(e.getPropertyName()))
{
if (table.isEditing())
processEditingStarted();
else
processEditingStopped();
}
}
Trying to clear the table model at processEditingStarted() does not work with the code bellow:
private void processEditingStarted()
{
SwingUtilities.invokeLater( this );
}
public void run()
{
row = table.convertRowIndexToModel( table.getEditingRow() );
column = table.convertColumnIndexToModel( table.getEditingColumn() );
oldValue = table.getModel().getValueAt(row, column);
newValue = null;
table.getModel().setValueAt(null, row, column);
table.updateUI();
}
However the editor content keeps the former value.
Does someone has clues to hide the current value of the cell during edition?
Optionnaly it should be able to restore the former cell content if the user did not actually modify the value.

I"ve never seen a spreadsheet remove data when you start editing a cell.
Table Select All Editor shows a different approach.

I did it like this. First I am using the event keyReleased and then getting the row and column number on which I am working and then setting the value at that row. Code goes like this.
private void purchases_TBLKeyReleased(java.awt.event.KeyEvent evt) {
int rowWorking = purchases_TBL.getSelectedRow();
int columnWorking = purchases_TBL.getSelectedColumn();
if(columnWorking==3){
model.setValueAt(null, rowWorking, columnWorking);
}
}
This makes the third column of the table null as soon as I focus move on to that using keyboard.
Note: The same piece of code can be placed in MouseClicked event.

GWT CELLTABLE column's cell value updation

I am using gwt2.3
My celltable contains 10 rows, 5 columns.
All cells in 1st row is empty,editable.
Whenever user clicks on column cell lets say 1st row X 3rd column
then user will edit that cell say "xyz".
after that when user click on button: "update column cell" then xyz value set to all cell present in that column.
I am using different celltype in celltable.
How to set/update all cell value in that particular column/page whose 1st cell is edited
Any help or guidance in this matter would be appreciated

Create a FieldUpdater in order to push back the changes to your Domain object. Then in the onClick callback of your button update your List with the values from the first row.
For example for an arbitrary TextInputColumn which takes a MyDTO class (can be any domain object) as the value type you can define following FieldUpdater:
myColumn.setFieldUpdater(new FieldUpdater() {
#Override
public void update(int index, MyDTO object, String value) {
// Push the changes into the MyDTO. At this point, you could send an
// asynchronous request to the server to update the database.
object.someField = value;
// Redraw the table with the new data.
table.redraw();
}
});
You have to set such a FieldUpdater for all 5 columns. (someField is the field in your DTO which you want to update).
Now in the onClick() callback of the button you have to update the actual list. Looks something like that:
update_column_cell.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
//Supose listDataProvider is the instance of your DataSource for your CellTable
List<MyDTO> list = listDataProvider.getList();
// get cell values for the first row (this is for one cell)
newSomeField = list.get(0).someField;
newSomeField2 = list.get(0).someField2;
for (int i = 1;i<list.size();i++) {
MyDTO dto = list.get(i);
if (newSomeField != null && newSomeField.isNotEmpty()) {
dto.someField = newSomeField;
}
if (newSomeField2 != null && newSomeField2.isNotEmpty()) {
dto.someField2 = newSomeField2;
}
}
}
})
This example only handles two fields of your DTO. You will probably have to extend it to cover all 5 fields you are showing as columns in your CellTable