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Cannot update JTable's values after data change using setValueAt

I've done JTable for simple schedule with visits.
It contains custom AbstractTableModel which shows three columns shown below.
The problem is that it is possible to initializate Table and to get desired look - but after data change there is no change in appearance of Table. Each button click takes data from database and sets fields in columns TYPE and STATE - depending on given hour and date of reservation.
What is more I'am able to insert new row at the end of table but cannot make visible existing value update.
I already read few similar topics but nothing helps in my case.
Thanks in advance for every suggestions.
[UPDATED] Working code illustrating the problem:
import java.awt.EventQueue;
import java.util.Vector;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.table.AbstractTableModel;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class ModelTest {
private JFrame frame;
private JTable tablePendingVisits;
private PendingVisitModel pendingVisitModel;
private JScrollPane scrollPanePendingVisits;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
ModelTest window = new ModelTest();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public ModelTest() {
frame = new JFrame();
frame.setBounds(100, 100, 450, 407);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
JButton btnChangeValue = new JButton("Change value at 9:00");
btnChangeValue.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
refreshTableModel();
}
});
btnChangeValue.setBounds(63, 308, 305, 23);
frame.getContentPane().add(btnChangeValue);
tablePendingVisits = new JTable();
scrollPanePendingVisits = new JScrollPane();
pendingVisitModel = new PendingVisitModel();
tablePendingVisits.setModel(pendingVisitModel);
scrollPanePendingVisits.setBounds(63, 36, 305, 246);
scrollPanePendingVisits.setViewportView(tablePendingVisits);
frame.getContentPane().add(scrollPanePendingVisits);
}
public void refreshTableModel(){
String[] sampleString = {"9:00", "Bobby", "Tables"};
// search for row with 9:00 and replace values in given columns
for (int i = 0; i < pendingVisitModel.getRowCount(); i++) {
if( sampleString[0].equals(pendingVisitModel.getValueAt(i, 0)) ) { // Change row values when both hours are equal
pendingVisitModel.setValueAt(sampleString[1], i, 1); // Change at type column
pendingVisitModel.setValueAt(sampleString[2], i, 2); // Change at status column
}
}
}
}
// Custom TableModel
class PendingVisitModel extends AbstractTableModel {
private static final long serialVersionUID = 1L;
private String[] columnNames = {"HOUR", "TYPE", "STATE"};
private Vector<String[]> data = new Vector<String[]>();
public PendingVisitModel() {
for(int i = 8; i<15; i++) {
data.add(new String[]{i+":00", "-", "Free"} );
data.add(new String[]{i+":15", "-", "Free"} );
data.add(new String[]{i+":30", "-", "Free"} );
data.add(new String[]{i+":45", "-", "Free"} );
}
}
public int getColumnCount() {
return columnNames.length;
}
public int getRowCount() {
return data.size();
}
public String getColumnName(int col) {
return columnNames[col];
}
public String getValueAt(int row, int col) {
String[] temp = data.get(row);
if(temp.length > 0 && col < 3)
return temp[col];
else
return null;
}
public void setValueAt(String[] value, int row, int col) {
String[] temp = data.get(row);
temp[col] = value[col];
data.set(row, temp);
fireTableRowsUpdated(row, row);
}
public void insertRow(String[] value) {
data.add(value);
fireTableRowsInserted(data.size(), data.size());
}
public void clearRows(){
data.clear();
fireTableDataChanged();
}
public void removeAllEntry(){
data.clear();
fireTableDataChanged();
}
public boolean isCellEditable(int row, int col) {
return false;
}
#Override
public Class<String> getColumnClass(int colNum) {
return String.class;
}
}

PendingVisitModel pendingVisitModel = new PendingVisitModel();
It looks to me like the pendingVisitModel is defined as a local variable. This is the model you add to the table.
The refreshTableModel() method is referencing a pendingVisitModelvariable, but I would guess this is an instance variable that is NOT used by the table.
Get rid of local instance of your pendingVisitModel.
fireTableDataChanged();
Also don't keep using firTableDataChanged in all your TableModel methods. The API provides other methods that are more appropriate for different events.
Edit:
public void setValueAt(String[] value, int row, int col) {
You did not override the setValueAt(...) method. The value parameter is an Object not a String array.
Whenever you override a method of a class you should use the #Override annotation before the method. This way the compiler will give you an error if you override a method incorrectly (saving hours of frustration...).
#Override
public void setValueAt(Object value, int row, int col) {

JComboBox in Custom table model

I have got question about adding JComboBox, to Column in Custom table model which extends ObjectTableModel (Table is OmniJTable). I work on it 2 days and cannot solve this problem.
One thing I solved is displaying JComboBox in Column, but right now I have got problem with selecting anything from it (seems it's not editable, and anything like "setEditable()" not working).
Here is code which one I add jComboBox to my OmniJTable with ObjectTableModel.
class CheckBoxCellRenderer extends JComboBox implements TableCellRenderer {
JComboBox combo;
public CheckBoxCellRenderer(JComboBox comboBox) {
this.combo = new JComboBox();
for (int i=0; i<comboBox.getItemCount(); i++){
combo.addItem(comboBox.getItemAt(i));
}
}
#Override
public Component getTableCellRendererComponent(JTable jtable, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
combo.setSelectedItem(value);
return combo;
}
}
private void addComboBoxToStatusColumn(JTable table)
{
final int statusColumnIndex = bazaTelefonowOmniJTable.getColumnModel().getColumnIndex("Status");
TableColumn tmpColum = bazaTelefonowOmniJTable.getColumnModel().getColumn(statusColumnIndex);
final JComboBox comboBox = new JComboBox();
comboBox.setEditable(true);
comboBox.setEnabled(true);
loadRecordStatusFromDictionary(comboBox);
DefaultCellEditor defaultCellEditor=new DefaultCellEditor(comboBox);
tmpColum.setCellEditor(defaultCellEditor);
tmpColum.setCellRenderer(new CheckBoxCellRenderer(comboBox));
bazaTelefonowOmniJTable.setEditable(true);
//table.repaint();
}
As i said, this one adding jComboBox to Column, but i don't know how to make this one to allow me to choose items in jComboBox.
PS: Sry for my english, it's not my primary language.

The simplest thing is not to add a CellRenderer. In that case, the Table renders it as a Label and when clicked the combo box is shown. Here is an example:
package snippet;
import java.awt.Component;
import javax.swing.DefaultCellEditor;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
public class JTableTest extends JFrame {
public JTableTest() {
super(JTableTest.class.getName());
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
initComponents();
}
private void initComponents() {
JTable table = new JTable(new Object[][] { { "1", "One" }, { "2", "Two" } }, new Object[] { "Column One", "Status" });
addComboBoxToStatusColumn(table);
add(new JScrollPane(table));
pack();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override public void run() {
new JTableTest().setVisible(true);
}
});
}
private void addComboBoxToStatusColumn(JTable table) {
final int statusColumnIndex = table.getColumnModel().getColumnIndex("Status");
TableColumn tmpColum = table.getColumnModel().getColumn(statusColumnIndex);
final JComboBox comboBox = new JComboBox();
loadRecordStatusFromDictionary(comboBox);
DefaultCellEditor defaultCellEditor = new DefaultCellEditor(comboBox);
tmpColum.setCellEditor(defaultCellEditor);
}
private void loadRecordStatusFromDictionary(JComboBox comboBox) {
comboBox.addItem("Two");
comboBox.addItem("Four");
comboBox.addItem("Six");
}
}
You also need to override the isCellEditable method from your model.
model = DaneTableModel(some arg) {
public boolean isCellEditable(int row, int col) {
if(col == STATUS_COLUMN) return true ;
return false;
}
}

How do I make it possible to select text in a JTable cell with editing disabled?

Imagine I'm building an IRC client with Java and I'd like rich text in the chat view to show IRC colors and colored nicks. I'd like to build this with a JTable. I can do that, but the text is then not selectable. Making the table editable doesn't make sense.
I've also investigated:
TextArea - no rich text formatting
JEditPane - can't append, only replace which is bad performance wise
JList - can't select text
So I got a table working I just need the text to be selectable without making it editable. I'd also would only like the text contents, and none of the HTML to be copied into the clipboard upon copying the text selection.
I have tried various iterations of setRowSelectionAllowed(), setColumnSelectionEnabled() and setCellSelectionEnabled() and setSelectionMode the table model returns false for isCellEditable(). Nothing has made the text selectable.
EDIT: as per answer 1 I was wrong about text editor panes so I'm trying those solutions.

I don't know why you don't want to use a JTextPane or JEditorPane. You insert text by its document. Examples here --> How to use Editor Panes and Text Panes.
But for your purpose you can for example do something like this. I override changeSelection to selectAll text when is clicking, the cells are editable but its cellEditors are not editable.
public class JTableTest {
private final DefaultCellEditor cellEditor;
private final JTextField textfield;
private JPanel panel;
private MyTableModel tableModel = new MyTableModel();
private JTable table = new JTable() {
#Override
public TableCellEditor getCellEditor(int row, int column) {
return JTableTest.this.cellEditor;
}
#Override
public void changeSelection(
final int row, final int column, final boolean toggle, final boolean extend) {
super.changeSelection(row, column, toggle, extend);
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
if ((getCellEditor(row, column) != null && !editCellAt(row, column))) {
JTextField textfield=(JTextField)JTableTest.this.cellEditor.getComponent();
textfield.selectAll();
}
}
});
}
};
public JTableTest() {
JScrollPane scroll = new JScrollPane(table);
table.setModel(tableModel);
panel = new JPanel(new BorderLayout());
panel.add(scroll, BorderLayout.CENTER);
textfield = new JTextField();
textfield.setEditable(Boolean.FALSE);
textfield.setBorder(null);
cellEditor = new DefaultCellEditor(textfield);
tableModel.insertValue(new ItemRow("nonEditable", "Editable"));
}
private class ItemRow {
private String column1;
private String column2;
public ItemRow(String column1, String column2) {
this.column1 = column1;
this.column2 = column2;
}
public String getColumn1() {
return column1;
}
public void setColumn1(String column1) {
this.column1 = column1;
}
public String getColumn2() {
return column2;
}
public void setColumn2(String column2) {
this.column2 = column2;
}
}
private class MyTableModel extends AbstractTableModel {
public static final int COLUMN1_INDEX = 0;
public static final int COLUMN2_INDEX = 1;
private final List<ItemRow> data = new ArrayList<>();
private final String[] columnsNames = {
"Column1",
"Column2",};
private final Class<?>[] columnsTypes = {
String.class,
String.class
};
public MyTableModel() {
super();
}
#Override
public Object getValueAt(int inRow, int inCol) {
ItemRow row = data.get(inRow);
Object outReturn = null;
switch (inCol) {
case COLUMN1_INDEX:
outReturn = row.getColumn1();
break;
case COLUMN2_INDEX:
outReturn = row.getColumn2();
break;
default:
throw new RuntimeException("invalid column");
}
return outReturn;
}
#Override
public void setValueAt(Object inValue, int inRow, int inCol) {
System.out.println("Gets called ");
if (inRow < 0 || inCol < 0 || inRow >= data.size()) {
return;
}
ItemRow row = data.get(inRow);
switch (inCol) {
case COLUMN1_INDEX:
row.setColumn1(inValue.toString());
break;
case COLUMN2_INDEX:
row.setColumn2(inValue.toString());
break;
}
fireTableCellUpdated(inRow, inCol);
}
#Override
public int getRowCount() {
return data.size();
}
#Override
public int getColumnCount() {
return columnsTypes.length;
}
#Override
public String getColumnName(int inCol) {
return this.columnsNames[inCol];
}
#Override
public Class<?> getColumnClass(int columnIndex) {
return this.columnsTypes[columnIndex];
}
/**
*
* #param row
*/
public void insertValue(ItemRow row) {
data.add(row);
fireTableRowsInserted(data.size() - 1, data.size() - 1);
}
#Override
public boolean isCellEditable(int rowIndex, int columnIndex) {
return true;
}
}
private static void createAndShowGUI(final Container container, final String title) {
//Create and set up the window.
JFrame frame = new JFrame(title);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(Boolean.TRUE);
frame.add(container);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String args[]) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
createAndShowGUI(new JTableTest().panel, "Test");
}
});
}
}

I accomplished this by enabling the editing and then making the component responsible for the edition ignore any changes. For this I created a TableCellEditor and intercepted the key types to the JTextField, the component used for editing.
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.AbstractCellEditor;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellEditor;
public class TableCellSelectionTest
{
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable() {
public void run()
{
new TableCellSelectionTest().initUI();
}
});
}
public void initUI()
{
JFrame frame = new JFrame();
int N = 5;
int M = 3;
Object[][] data = new Object[N][M];
for (int i = 0; i < N; ++i)
{
for (int j = 0; j < M; ++j)
{
data[i][j] = "This is the cell (" + i + ", " + j +")";
}
}
String[] columnNames = { "Column 1", "Column 2", "Column 3" };
DefaultTableModel model = new DefaultTableModel(data, columnNames);
final MyTableCellEditor editor = new MyTableCellEditor();
JTable table = new JTable(model) {
#Override
public TableCellEditor getCellEditor(int row, int column)
{
return editor;
}
};
frame.add(new JScrollPane(table), BorderLayout.CENTER);
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
class MyTableCellEditor extends AbstractCellEditor implements
TableCellEditor
{
Object _value;
#Override
public Object getCellEditorValue()
{
return _value;
}
#Override
public Component getTableCellEditorComponent(JTable table,
Object value, boolean isSelected, int row, int column)
{
_value = value;
JTextField textField = new JTextField(_value.toString());
textField.addKeyListener(new KeyAdapter()
{
public void keyTyped(KeyEvent e) {
e.consume(); //ignores the key
}
#Override
public void keyPressed(KeyEvent e)
{
e.consume();
}});
textField.setEditable(false); //this is functionally irrelevent, makes slight visual changes
return textField;
}
}
}

I tried both the answers here... but one problem at least is that you can tell when you've entered the "editing" mode.
This might be of interest... uses a combination of Editor magic and cheeky rendering to make it look like no editing is going on: editor's click-count-to-start is set to 1, and the component (JTextPane) delivered by the editor's method does setEditable( false ).
If this tickles your fancy, you might be interested at looking at my implementation of a JTable which adjusts (perfectly, harnessing the JTextPane's powerful wrapping power) the row height to the text, for individual rows, including when you change the columns: How to wrap lines in a jtable cell?
public class SelectableNonEditableTableTest {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame main_frame = new JFrame();
main_frame.setPreferredSize(new Dimension(1200, 300));
main_frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ArrayList<String> nonsense = new ArrayList<String>(
Arrays.asList(
"Lorem ipsum dolor sit amet, sed dolore vivendum ut",
"pri an soleat causae doctus.",
"Alienum abhorreant mea ea",
"cum malorum diceret ei. Pri oratio invidunt consequat ne.",
"Ius tritani detraxit scribentur et",
"has detraxit legendos intellegat at",
"quo oporteat constituam ex"));
JTable example_table = new JTable(10, 4);
example_table.setRowHeight( example_table.getRowHeight() * 2 );
DefaultCellEditor cell_editor = new SelectableNonEditableCellEditor(
new JTextField());
cell_editor.setClickCountToStart(1);
example_table.setDefaultEditor(Object.class, cell_editor);
TableCellRenderer renderer = new SelectableNonEditableTableRenderer();
example_table.setDefaultRenderer(Object.class, renderer);
for (int i = 0; i < 10; i++) {
example_table.setValueAt(nonsense.get(i % nonsense.size()),
i, i % 4);
}
main_frame.getContentPane().add(new JScrollPane(example_table));
main_frame.pack();
main_frame.setVisible(true);
}
});
}
}
class SelectableNonEditableCellEditor extends DefaultCellEditor {
public SelectableNonEditableCellEditor(JTextField textField) {
super(textField);
}
public Component getTableCellEditorComponent(JTable table, Object value,
boolean isSelected, int row, int col) {
Component comp = super.getTableCellEditorComponent(table, value,
isSelected, row, col);
if (value instanceof java.lang.String) {
DefaultStyledDocument sty_doc = new DefaultStyledDocument();
try {
sty_doc.insertString(0, (String) value, null);
} catch (BadLocationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
JTextPane jtp_comp = new JTextPane(sty_doc);
jtp_comp.setEditable(false);
return jtp_comp;
}
return comp;
}
}
class SelectableNonEditableTableRenderer extends JTextPane implements
TableCellRenderer {
#Override
public Component getTableCellRendererComponent(JTable table, Object value,
boolean isSelected, boolean hasFocus, int row, int column) {
if (value instanceof DefaultStyledDocument) {
setDocument((DefaultStyledDocument) value);
} else {
setText((String) value);
}
return this;
}
}

Maybe you can implement your own TableCellRenderer that extends JTextField in your table.

How do you disallow Drag and Drop between two JTables?

I have two JTables, and they are set up so that you can drag and drop the rows within each JTable. The problem is that it lets me drag a row from one JTable to the other JTable, and I am trying to figure out how to stop that. I only want the user to be able to drag and drop a row within that same JTable.
In other words, when I drag a row outside the current table and hover the mouse over the empty panel space, the mouse cursor displays a circle with a diagonal line through it, which is what I want. However, when I drag the mouse over the other table, it displays the small rectangular "drop" icon, which is what I am trying to block. When the user tries to drag this row on top of other table, I would like the small circle with diagonal line to appear.
This is a working example that demonstrates the problem:
import java.awt.Cursor;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.dnd.DragSource;
import java.util.ArrayList;
import java.util.List;
import javax.activation.ActivationDataFlavor;
import javax.activation.DataHandler;
import javax.swing.DropMode;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.ListSelectionModel;
import javax.swing.TransferHandler;
import javax.swing.table.AbstractTableModel;
public class JTableDnD extends JFrame
{
private JTable tableA;
private JTable tableB;
public JTableDnD()
{
// *** Create First Table ***
List<Object[]> dataA = new ArrayList<Object[]>();
dataA.add(new Object[] {"A1", "A1"});
dataA.add(new Object[] {"A2", "A2"});
dataA.add(new Object[] {"A3", "A3"});
List<String> columnsA = new ArrayList<String>();
columnsA.add("Column 1");
columnsA.add("Column 2");
tableA = new JTable(new TableModel(columnsA, dataA));
tableA.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
tableA.setDragEnabled(true);
tableA.setDropMode(DropMode.INSERT_ROWS);
tableA.setFillsViewportHeight(true);
tableA.setTransferHandler(new TableTransferHandler(tableA));
JScrollPane scrollPaneA = new JScrollPane(tableA);
// *** Create Second Table ***
List<Object[]> dataB = new ArrayList<Object[]>();
dataB.add(new Object[] {"B1", "B1"});
dataB.add(new Object[] {"B2", "B2"});
dataB.add(new Object[] {"B3", "B3"});
List<String> columnsB = new ArrayList<String>();
columnsB.add("Column 1");
columnsB.add("Column 2");
tableB = new JTable(new TableModel(columnsB, dataB));
tableB.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
tableB.setDragEnabled(true);
tableB.setDropMode(DropMode.INSERT_ROWS);
tableB.setFillsViewportHeight(true);
tableB.setTransferHandler(new TableTransferHandler(tableB));
JScrollPane scrollPaneB = new JScrollPane(tableB);
// *** Add ScrollPanes to Panel ***
this.getContentPane().setLayout(new FlowLayout());
add(scrollPaneA);
JPanel emptyPanel = new JPanel();
emptyPanel.setPreferredSize(new Dimension(100, 200));
add(emptyPanel);
add(scrollPaneB);
} // end JTableDnD constructor
private static void createAndShowGUI()
{
JFrame frame = new JTableDnD();
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public static void main(String[] args)
{
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
interface Reorderable
{
public void reorder(int from, int to);
}
class TableModel extends AbstractTableModel implements Reorderable
{
private List<String> columnNames;
private List<Object[]> data;
public TableModel(List<String> columnNames, List<Object[]> data)
{
super();
this.columnNames = columnNames;
this.data = data;
}
#Override
public void reorder(int from, int to)
{
if (from < to)
{
to--;
}
Object[] row = data.remove(from);
data.add(to, row);
fireTableDataChanged();
}
#Override
public int getRowCount()
{
return data.size();
}
#Override
public int getColumnCount()
{
return columnNames.size();
}
#Override
public String getColumnName(int column)
{
return columnNames.get(column);
}
#Override
public Object getValueAt(int rowIndex, int columnIndex)
{
return data.get(rowIndex)[columnIndex];
}
} // end TableModel
class TableTransferHandler extends TransferHandler
{
private final DataFlavor localObjectFlavor = new ActivationDataFlavor(Integer.class, DataFlavor.javaJVMLocalObjectMimeType, "Integer Row Index");
private JTable table = null;
public TableTransferHandler(JTable table)
{
this.table = table;
}
#Override
protected Transferable createTransferable(JComponent component)
{
return new DataHandler(new Integer(table.getSelectedRow()), localObjectFlavor.getMimeType());
}
#Override
public boolean canImport(TransferHandler.TransferSupport support)
{
boolean b = support.getComponent() == table &&
support.isDrop() &&
support.isDataFlavorSupported(localObjectFlavor);
table.setCursor(b ? DragSource.DefaultMoveDrop : DragSource.DefaultMoveNoDrop);
return b;
}
#Override
public int getSourceActions(JComponent component)
{
return TransferHandler.COPY_OR_MOVE;
}
#Override
public boolean importData(TransferHandler.TransferSupport support)
{
JTable target = (JTable) support.getComponent();
JTable.DropLocation dropLocation = (JTable.DropLocation) support.getDropLocation();
int index = dropLocation.getRow();
int max = table.getModel().getRowCount();
if (index < 0 || index > max)
{
index = max;
}
target.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
try
{
Integer rowFrom = (Integer) support.getTransferable().getTransferData(localObjectFlavor);
if (rowFrom != -1 && rowFrom != index)
{
((Reorderable) table.getModel()).reorder(rowFrom, index);
if (index > rowFrom)
{
index--;
}
target.getSelectionModel().addSelectionInterval(index, index);
return true;
}
}
catch (Exception e)
{
e.printStackTrace();
}
return false;
}
#Override
protected void exportDone(JComponent component, Transferable transferable, int action)
{
if (action == TransferHandler.MOVE)
{
table.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
}
}
} // end TableTransferHandler
I believe I need to add some extra logic to the canImport() method to make sure that the row that is being dropped is from that same table, but I can't seem to figure it out. I've tried inspecting the data inside the TransferSupport object that gets passed into canImport(), but it does not seem to have any function that returns the exact JTable object source.

In the simplified Swing DnD, there is no support for getting at the source of the transferable. The component returned by TransferSupport` is the target of the drop, that is the component that somehow should handle the associated transferable. So if you have a per-component TransferHandler configured with a particular table, the support's component will always be that same table instance and your check will be true trivially.
If you want to enable/disable dropping based on the sender, you'll have to provide it on a per-drag basis: a drag starts in exportAsDrag and ends in exportDone, so you can set/null the sender in those.
#Override
protected void exportDone(JComponent component,
Transferable transferable, int action) {
table = null;
}
#Override
public void exportAsDrag(JComponent comp, InputEvent e, int action) {
table = (JTable) comp;
super.exportAsDrag(comp, e, action);
}
Now you can re-use the same instance of the handler across several instances of table:
TableTransferHandler handler = new TableTransferHandler();
tableA.setTransferHandler(handler);
tableB.setTransferHandler(handler);
As an aside: I wouldn't fiddle with the cursors, they are supporsed to be under complete control of the dnd subsystem.

How to make only one checkbox selectable in JTable Column

I am using DefaultTableModel as follows:
DefaultTableModel model = new DefaultTableModel (COLUMNS, 0 )
{
#Override
public boolean isCellEditable(int row, int column)
{
return (getColumnName(column).equals("Selected"));
}
public Class getColumnClass(int columnIndex)
{
if(getColumnName(columnIndex).equals("Selected"))
return Boolean.class;
return super.getColumnClass(columnIndex);
}
};
Now I want to make only one checkbox selectable in the column "Selected". How can this be done. I have tried following method also but its not working.
public void fireTableCellUpdated(int row,int column)
{
if(getColumnName(column).equals("Selected"))
{
for(int i = 0; i<getRowCount() && i!=row;i++)
setValueAt(Boolean.FALSE, row, column);
}
}

#eatSleepCode wrote #mKorbel can you please give example code for implementing setValueAt method.
code for (OP used) DefaultTableModel,
for code based on AbstractTableModel is required to hold code ordering for notifier fireTableCellUpdated(rowIndex, columnIndex);, because/otherwise nothing will be repainted in JTables view,
there are a few important differencies betweens those two models and its notifiers, and (my view) there isn't reason to bothering with and to use AbstractTableModel for basic stuff (99pct of table models)
. . . . . . . .
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableModel;
public class TableRolloverDemo {
private JFrame frame = new JFrame("TableRolloverDemo");
private JTable table = new JTable();
private String[] columnNames = new String[]{"Column"};
private Object[][] data = new Object[][]{{false}, {false}, {true}, {true},
{false}, {false}, {true}, {true}, {false}, {false}, {true}, {true}};
public TableRolloverDemo() {
final DefaultTableModel model = new DefaultTableModel(data, columnNames) {
private boolean ImInLoop = false;
#Override
public Class<?> getColumnClass(int columnIndex) {
return Boolean.class;
}
#Override
public boolean isCellEditable(int rowIndex, int columnIndex) {
return true;
}
#Override
public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
if (columnIndex == 0) {
if (!ImInLoop) {
ImInLoop = true;
Boolean bol = (Boolean) aValue;
super.setValueAt(aValue, rowIndex, columnIndex);
for (int i = 0; i < this.getRowCount(); i++) {
if (i != rowIndex) {
super.setValueAt(!bol, i, columnIndex);
}
}
ImInLoop = false;
}
} else {
super.setValueAt(aValue, rowIndex, columnIndex);
}
}
};
table.setModel(model);
table.setPreferredScrollableViewportSize(table.getPreferredSize());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new JScrollPane(table));
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
TableRolloverDemo tableRolloverDemo = new TableRolloverDemo();
}
});
}
}

You get an stack overflow exception because setValueAt() method triggers fireTableCellUpdated() method once again and again.
Instead, try using a table listener which would listen to check box's value change and would set all other check boxes' value to false.

You can create your own custom cell editor that joins all check boxes in a column in a ButtonGroup. here's how:
public class VeryComplicatedCellEditor extends DefaultCellEditor {
private ArrayList<ButtonGroup> groups;
public getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {
JCheckBox checkBox = new JCheckBox();
growToSize(column);
groups.get(column).add(checkBox);
return checkBox;
}
private growToSize(int size) {
groups.ensureCapacity(size);
while (groups.size() < size)
groups.add(new ButtonGroup());
}
}
There are some complications that come from the fact that we don't know how big the table is, which are mostly taken care of in the growToSize method.
The way this works is by maintaining a list of ButtonGroups, one for each column. The editor component for each cell is added to the button group for its column.