Updating value in a jtable cell

hi
I have a JTable where user enters numbers into the cells and then clicks on a button which reads all these numbers and prints a number which is calculated using all these values
my problem is that the very last cell which data is typed into is not "seen" and the only way for the system to see it is if i remove focus from that cell before i press the button.
is there anyway for me to be able to press that button and the system read the last cell without having to click of that last cell before hand?
the way i obtain the value in each cell is table.getValueAt(i , j)
does anyone understand what i mean? its kinda hard to explain.
thanks alot

PhHein wrote:
corlettk wrote:
PhHein wrote:
corlettk wrote:
Edited by: corlettk on 6/04/2009 22:33 ~~ Mr Hein has already posted a better way... A day late and a penny short ;-)I would have expected you to be less formal at that time of the day ;-)It's a weeknight.Ooh, I didn't think that mattered in Australia(?) . ;-)We need to give the breweries three days a week to restock... Traditionaly that's Monbluddyday, Tuesbluddyday, and Wedbluddynesday... It's all good Thursday through Sunday though, as long as your äss isn't on fire, or twenty feet below flood level, and you can resist the urge to tongue-pash a sting-ray, that is.
Cheers. Keith.

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How to force check right value of a JTable cell?

Hi,
I have a JTable with a column that must have a value no empty and between 0 and 100. I made a sample with only one column for simplicity.
The code works fine when the user types some value. However, when the user press ENTER to go to next column, without editing the cell, no checks run.
I have also other column that the user may type a part of a name and the system must find the full name of a person. In this column, if user uses ENTER without editing the cell, the same problem ocurrs.
The simplistic code is here, runnable:
import java.awt.*;
import java.util.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.table.*;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.text.NumberFormat;
import java.text.ParseException;
import javax.swing.text.DefaultFormatterFactory;
import javax.swing.text.NumberFormatter;
public class TableCheckCell extends JFrame {
/** Creates a new instance of TableCheckCell */
public TableCheckCell() {
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    Object[][] data =
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      {new Integer(-1)},
      {new Integer(-1)},
      {new Integer(-1)}
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    JTable table = new JTable(model);
    table.setPreferredScrollableViewportSize(table.getPreferredSize());
    JScrollPane scrollPane = new JScrollPane( table );
    getContentPane().add( scrollPane );
    TableColumn col = table.getColumnModel().getColumn(0);
    col.setCellEditor(new CellIntegerEditor(CellIntegerEditor.CHECKMINMAX,0,100));
public static void main(String[] args) {
    TableCheckCell frame = new TableCheckCell();
    frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
    frame.pack();
    frame.setLocationRelativeTo( null );
    frame.setVisible(true);
* Implements a cell editor that uses a formatted text field
* to edit Integer values.
class CellIntegerEditor extends DefaultCellEditor {
public static final int NOCHECK = 0;
public static final int CHECKMINMAX = 1;
public static final int CHECKMIN = 2;
public static final int CHECKMAX = 3;
JFormattedTextField ftf;
NumberFormat integerFormat;
private int checkinterv;
private Integer minimum, maximum;
private boolean DEBUG = false;
public CellIntegerEditor(int checkinterv, int min, int max) {
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    maximum = new Integer(max);
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            ftf.postActionEvent(); //inform the editor
        } else try {              //The text is valid,
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public Component getTableCellEditorComponent(JTable table,
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      return o;
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        System.out.println("getCellEditorValue: o isn't a Number");
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      } catch (ParseException exc) {
        System.err.println("getCellEditorValue: can't parse o: " + o);
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//setting the value if it is and complaining if
//it isn't. If it's OK for the editor to go
//away, we need to invoke the superclass's version
//of this method so that everything gets cleaned up.
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        ftf.commitEdit();
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   * bad. Returns true if the user elects to revert to
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protected boolean userSaysRevert() {
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      msg = "Value must be <= " + maximum + ".";
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}Then, I'd like to know if there is any way to check the user typed ENTER to go out of the cell, check the value of the cell and, if it is wrong, to come back to the cell, forcing the user to type a right value.

Editing to force the entry of data in a cell is typically done when you press a button to process the data. It doesn't make sense to "edit" the cell when the user presses enter to go to the next cell. What if the user never places focus on a particular cell. Then the cell will never be edited.
To force a user to enter a valid value once they have started editing you can do something like this:
http://forum.java.sun.com/thread.jspa?forumID=57&threadID=575309
But you can't force a user to visit every cell in the table so you need to handle that as described above.

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Hello all,
I'm trying to implement a setValueAt method using an arrayList.....no success.What listeners should I have set up(For JTable or my table model)? I am new at this and I'm trying to update the JTable cells after a query from some db. Could anyone help?
When trying to change the a value in the table I get these errors:
"Exception occurred during event dispatching:
java.lang.ClassCastException: java.lang.String
at CachingResultSetTableModel.getValueAt(CachingResultSetTableModel.java:37)
at javax.swing.JTable.getValueAt(JTable.java:1711)
at javax.swing.JTable.prepareRenderer(JTable.java:3530)"
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I would think that everone who starts off with JTable will have a couple of concept problems. I am also going thru this learnig curve. It looks to me ( the blind leading the blind etc) like your basic table has strange data in it. The problem is occuring when the JTable is trying to setup the data from the table model.
I don't think its anything to do with setValueAt.
I kept going back to TableMap, TableSorter and JDBCAdaptor examples and copying the code from them to come right.> I debug by putting a System.out .... in all the methods until I get to where the code is giving trouble.
Good luck [email protected]
Hello all,
>
I'm trying to implement a setValueAt method using an
arrayList.....no success.What listeners should I have
set up(For JTable or my table model)? I am new at
this and I'm trying to update the JTable cells after a
query from some db. Could anyone help?
When trying to change the a value in the table I get
these errors:
"Exception occurred during event dispatching:
java.lang.ClassCastException: java.lang.String
at
CachingResultSetTableModel.getValueAt(CachingResultSetT
bIleModel.java:37)
at javax.swing.JTable.getValueAt(JTable.java:1711)
at
javax.swing.JTable.prepareRenderer(JTable.java:3530)"
public void setValueAt(Object avalue, int r, int c){
if(r < cache.size()){
row[c] = (Object[])cache.set(r, avalue);
fireTableCellUpdated(r, c);
}//setValueAt
*********For reference here's the getValueAt
method*************************
public Object getValueAt(int r, int c){
if(r < cache.size()){
row = (Object[])cache.get(r);
return row[c];
else
return null;
}//getValueAt

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Once I tab out of that cell, go back to the same cell, edit the value again and tab out. It still shows me old value, not the updated one.
I'm using putClientProperty("terminateEditOnFocusLost", Boolean.TRUE) to recognise the cell value without focus lost.
Does this cause any problem ???
Thanks in advance
Kapil

then what might be the problem of value not getting deleted ??
Code is:
public class MyTableCellEditor extends AbstractCellEditor
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private JTextField component = null;
//This method is called when a cell value is edited by the user.
public Component getTableCellEditorComponent(JTable table, Object value,
boolean isSelected, int rowIndex, int vColIndex) {
component = new JTextField();
System.out.println("value*************** "+value);
System.out.println("Component value*************** "+component.getText());
if(value != null){
component.setText(value.toString());
else{
component.setText("");
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return component;
// This method is called when editing is completed.
// It must return the new value to be stored in the cell.
public Object getCellEditorValue() {
return component.getText();
public boolean shouldSelectCell(EventObject anEvent) {
return false;
}

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If my user changes the value in cell 'A', I'd like to change the value in cell 'B' to the results of a calculation performed using the new value in A with the present ( prior to changing ) value in B.
Example:
Cell: suggested_sell_price
Cell: cost_this_item
A change in the cost_this_item cell would be reflected in the suggested_sell_price,(upon hitting enter the values are stored in the DB)
Any suggestions would be greatly appreciated,

Thanks for the suggestions. I'm posting a test program of what I have at the moment, it has some of the behavior I'm looking for, but I can't seem to get the new value of an aedited cell and set the table model with the new value.
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.table.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class TE extends JFrame
     String[] cols = {"VAL_1", "VAL_2", "VAL_3"};
     Object[][] filler = {
                                   {new Double(100.00), new Double(100.00), new Double(100.00)},
                                   {new Double(200.00), new Double(200.00), new Double(200.00)},
                                   {new Double(400.00), new Double(400.00), new Double(400.00)}
     JTable table;
     TE(String title)
               super(title);
               this.setDefaultCloseOperation(EXIT_ON_CLOSE);
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               mtm.setColumnIdentifiers(cols);
               int nRows = filler.length;
               for(int i = 0; i < nRows; ++i)
                         mtm.setValueAt(filler[0], 0, i);
                         mtm.setValueAt(filler[1][i], 1, i);
                         mtm.setValueAt(filler[2][i], 2, i);
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               table.getColumnModel().getColumn(1).setCellEditor(new SimpleCellEditor());
               table.getColumnModel().getColumn(2).setCellEditor(new SimpleCellEditor());
               //table.getColumnModel().getColumn(2).setCellEditor(new SimpleCellEditor());
               JScrollPane jsp = new JScrollPane(table);
               Container c = getContentPane();
               c.add(jsp);
               setSize(300,300);
               setVisible(true);
     class MyMouseListener extends MouseAdapter
               public void mouseClicked(MouseEvent e)
                    if(e.getClickCount() == 2)
                              table.setValueAt("QQQQQQQ", 1,1);
class SimpleCellEditor extends AbstractCellEditor implements TableCellEditor, ActionListener
     JTextField tf = new JTextField();
     TableModel tm = table.getModel();
     protected EventListenerList listenerList = new EventListenerList();
     protected ChangeEvent changeEvent = new ChangeEvent(this);
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               super();
               tf.addMouseListener(new MyMouseListener());
               tf.addActionListener(this);
public void addCellEditorListener(CellEditorListener listener) {
listenerList.add(CellEditorListener.class, listener);
public void removeCellEditorListener(CellEditorListener listener) {
listenerList.remove(CellEditorListener.class, listener);
protected void fireEditingStopped()
          CellEditorListener listener;
          Object[] listeners = listenerList.getListenerList();
          for (int i = 0; i < listeners.length; i++)
               if (listeners[i] == CellEditorListener.class)
                         listener = (CellEditorListener) listeners[i + 1];
                         listener.editingStopped(changeEvent);
protected void fireEditingCanceled()
     CellEditorListener listener;
          Object[] listeners = listenerList.getListenerList();
               for (int i = 0; i < listeners.length; i++)
               if (listeners[i] == CellEditorListener.class)
                    listener = (CellEditorListener) listeners[i + 1];
                    listener.editingCanceled(changeEvent);
public void cancelCellEditing()
          fireEditingCanceled();
public boolean stopCellEditing()
          fireEditingStopped();
          return true;
public boolean isCellEditable(EventObject event)
          return true;
     public boolean shouldSelectCell(EventObject event)
     return true;
public Object getCellEditorValue()
     return tf.getText();
public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column)
     if(tf.hasFocus() == true)
               tf.setBackground(Color.CYAN);
          return tf;
     public void actionPerformed(ActionEvent e)
          int row = table.getSelectedRow();
          int col = table.getSelectedColumn();
          double nVal = 0.00;
          Object currCostVal;
          Object currSellVal;
          Double costVal;
          Double sellVal;
          double newSellVal;
          double currentCost;
          if(table.getSelectedColumn() == 1)
               currCostVal = table.getValueAt(row, col+1);
               currSellVal = table.getValueAt(row, col);
               costVal = new Double(currCostVal.toString());
               currentCost = costVal.doubleValue();
               sellVal = new Double(currSellVal.toString());
               newSellVal = sellVal.doubleValue();
               nVal = newSellVal*currentCost*100/100;
               System.out.println("Recommended sell-price after change: " + nVal);
          }else if(table.getSelectedColumn() == 2 )
                    currCostVal = table.getValueAt(row, col);
                    currSellVal = table.getValueAt(row, col-1);
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                    currentCost = costVal.doubleValue();
                    sellVal = new Double(currSellVal.toString());
                    newSellVal = sellVal.doubleValue();
                    nVal = newSellVal*currentCost*100/100;
                    System.out.println("Recommended sell-price after change: " + nVal);
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}// end simple cell editor
class MTM extends DefaultTableModel
          MTM(int rows, int cols)
                    super(rows, cols);
public static void main(String args[])
          TE te = new TE("Test of table cell update");

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TIA,
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Manish -
Would you be able to post your idea?
I have a column in a table that I added
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or deselect the data. Sometimes when
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import java.awt.Component;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JLabel;
import javax.swing.JTable;
import javax.swing.table.TableCellRenderer;
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import javax.swing.JScrollPane;
import javax.swing.JTable;
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This is an example I published some while ago -
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Update JTable - Cell

i tried out the sample http://java.sun.com/docs/books/tutorial/uiswing/components/example-swing/TableDemo.java. if i enter a new value and klick into another cell of the table all works fine. if i click on the table header after editing the cell the old value appears in the cell. if i enter signs directly after the click on the table header the text appended to the old value of the edited cell.
i hope, anybody can help me.

Hmm, the suggestion given above appears to work when focus is gained on all other components, so the table header must have to logic to "cancel" cell editing. You can add your own MouseListener to "save" the edited data to the table header:
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D

I the forums 100s of times.Many thanks. If they had a decent search on this forum I might have found it as I did try.
Come to think of it - Sun have completely fcukd up this forum.

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Probably it's a stupid question but I have this problem:
I have a the necessity to build a JTable in which, when I edit a cell and I push a keyboard button, a new Frame opens to edit the content of the cell.
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What to do??
Thanks

Hi there
Depending on your table model you should normally change the "cell value" of the tablemodel.
This could look like:
JTable table = new JTable();
TableModel model = table.getModel();
int rowIndex = 0, columnIndex = 0;
model.setValueAt("This is a test", rowIndex, columnIndex);
The tablemodel should then fire an event to the view (i.e. JTable) and the table should be updated.
Hope this helps you

Problem in event handling of combo box in JTable cell

Hi,
I have a combo box as an editor for a column cells in JTable. I have a event listener for this combo box. When ever I click on the JTable cell whose editor is combo box,
I get the following exception,
Exception occurred during event dispatching:
java.lang.NullPointerException
     at javax.swing.plaf.basic.BasicTableUI$MouseInputHandler.setDispatchComponent(Unknown Source)
     at javax.swing.plaf.basic.BasicTableUI$MouseInputHandler.mousePressed(Unknown Source)
     at java.awt.AWTEventMulticaster.mousePressed(Unknown Source)
     at java.awt.Component.processMouseEvent(Unknown Source)
     at java.awt.Component.processEvent(Unknown Source)
     at java.awt.Container.processEvent(Unknown Source)
     at java.awt.Component.dispatchEventImpl(Unknown Source)
     at java.awt.Container.dispatchEventImpl(Unknown Source)
     at java.awt.Component.dispatchEvent(Unknown Source)
     at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
     at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
     at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
     at java.awt.Container.dispatchEventImpl(Unknown Source)
     at java.awt.Component.dispatchEvent(Unknown Source)
     at java.awt.EventQueue.dispatchEvent(Unknown Source)
     at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)
     at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
     at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
     at java.awt.EventDispatchThread.run(Unknown Source)
Can any one tell me how to over come this problem.
Thanks,
Raghu

Here's an example of the model I used in my JTable. I've placed 2 comboBoxes with no problems.
Hope this helps.
public class FileModel5 extends AbstractTableModel
public boolean isEditable = false;
protected static int NUM_COLUMNS = 3;
// initialize number of rows to start out with ...
protected static int START_NUM_ROWS = 0;
protected int nextEmptyRow = 0;
protected int numRows = 0;
static final public String file = "File";
static final public String mailName = "Mail Id";
static final public String postName = "Post Office Id";
static final public String columnNames[] = {"File", "Mail Id", "Post Office Id"};
// List of data
protected Vector data = null;
public FileModel5()
data = new Vector();
public boolean isCellEditable(int rowIndex, int columnIndex)
// The 2nd & 3rd column or Value field is editable
if(isEditable)
if(columnIndex > 0)
return true;
return false;
* JTable uses this method to determine the default renderer/
* editor for each cell. If we didn't implement this method,
* then the last column would contain text ("true"/"false"),
* rather than a check box.
public Class getColumnClass(int c)
return getValueAt(0, c).getClass();
* Retrieves number of columns
public synchronized int getColumnCount()
return NUM_COLUMNS;
* Get a column name
public String getColumnName(int col)
return columnNames[col];
* Retrieves number of records
public synchronized int getRowCount()
if (numRows < START_NUM_ROWS)
return START_NUM_ROWS;
else
return numRows;
* Returns cell information of a record at location row,column
public synchronized Object getValueAt(int row, int column)
try
FileRecord5 p = (FileRecord5)data.elementAt(row);
switch (column)
case 0:
return (String)p.file;
case 1:
return (String)p.mailName;
case 2:
return (String)p.postName;
catch (Exception e)
return "";
public void setValueAt(Object aValue, int row, int column)
FileRecord5 arow = (FileRecord5)data.elementAt(row);
arow.setElementAt((String)aValue, column);
fireTableCellUpdated(row, column);
* Returns information of an entire record at location row
public synchronized FileRecord5 getRecordAt(int row) throws Exception
try
return (FileRecord5)data.elementAt(row);
catch (Exception e)
throw new Exception("Record not found");
* Used to add or update a record
* @param tableRecord
public synchronized void updateRecord(FileRecord5 tableRecord)
String file = tableRecord.file;
FileRecord5 p = null;
int index = -1;
boolean found = false;
boolean addedRow = false;
int i = 0;
while (!found && (i < nextEmptyRow))
p = (FileRecord5)data.elementAt(i);
if (p.file.equals(file))
found = true;
index = i;
} else
i++;
if (found)
{ //update
data.setElementAt(tableRecord, index);
else
if (numRows <= nextEmptyRow)
//add a row
numRows++;
addedRow = true;
index = nextEmptyRow;
data.addElement(tableRecord);
//Notify listeners that the data changed.
if (addedRow)
nextEmptyRow++;
fireTableRowsInserted(index, index);
else
fireTableRowsUpdated(index, index);
* Used to delete a record
public synchronized void deleteRecord(String file)
FileRecord5 p = null;
int index = -1;
boolean found = false;
int i = 0;
while (!found && (i < nextEmptyRow))
p = (FileRecord5)data.elementAt(i);
if (p.file.equals(file))
found = true;
index = i;
} else
i++;
if (found)
data.removeElementAt(i);
nextEmptyRow--;
numRows--;
fireTableRowsDeleted(START_NUM_ROWS, numRows);
* Clears all records
public synchronized void clear()
int oldNumRows = numRows;
numRows = START_NUM_ROWS;
data.removeAllElements();
nextEmptyRow = 0;
if (oldNumRows > START_NUM_ROWS)
fireTableRowsDeleted(START_NUM_ROWS, oldNumRows - 1);
fireTableRowsUpdated(0, START_NUM_ROWS - 1);
* Loads the values into the combo box within the table for mail id
public void setUpMailColumn(JTable mapTable, ArrayList mailList)
TableColumn col = mapTable.getColumnModel().getColumn(1);
javax.swing.JComboBox comboMail = new javax.swing.JComboBox();
int s = mailList.size();
for(int i=0; i<s; i++)
comboMail.addItem(mailList.get(i));
col.setCellEditor(new DefaultCellEditor(comboMail));
//Set up tool tips.
DefaultTableCellRenderer renderer = new DefaultTableCellRenderer();
renderer.setToolTipText("Click for mail Id list");
col.setCellRenderer(renderer);
//Set up tool tip for the mailName column header.
TableCellRenderer headerRenderer = col.getHeaderRenderer();
if (headerRenderer instanceof DefaultTableCellRenderer)
((DefaultTableCellRenderer)headerRenderer).setToolTipText(
"Click the Mail Id to see a list of choices");
* Loads the values into the combo box within the table for post office id
public void setUpPostColumn(JTable mapTable, ArrayList postList)
TableColumn col = mapTable.getColumnModel().getColumn(2);
javax.swing.JComboBox combo = new javax.swing.JComboBox();
int s = postList.size();
for(int i=0; i<s; i++)
combo.addItem(postList.get(i));
col.setCellEditor(new DefaultCellEditor(combo));
//Set up tool tips.
DefaultTableCellRenderer renderer = new DefaultTableCellRenderer();
renderer.setToolTipText("Click for post office Id list");
col.setCellRenderer(renderer);
//Set up tool tip for the mailName column header.
TableCellRenderer headerRenderer = col.getHeaderRenderer();
if (headerRenderer instanceof DefaultTableCellRenderer)
((DefaultTableCellRenderer)headerRenderer).setToolTipText(
"Click the Post Office Id to see a list of choices");
}

Start or stop edit jtable cell editing

Hello,
I got a problem with the jtable DefaultModel isCellEditable.
If I set the IsCellEditable to false, I would not be able to enable the cell selection as and when I want it.
What I have in mind is the add a mouselister so that if the user select a row using fast left mouse click like the procedure shown below
private class MouseClickHandler extends MouseAdapter {
public void mouseClicked(MouseEvent event) {
int no_mouseclick = 0;
no_mouseclick = event.getClickCount();
if (no_mouseclick >= 2) {
int cur_row = 0;
cur_row = table.getSelectedRow();
// table.setColumnSelectionAllowed(true);
// table.setRowSelectionAllowed(true);
for (int i=0;i<table.getColumnCount();i++){
table.editCellAt(cur_row,i);
System.out.println("mouse row--->" + cur_row);
I could overwrite the IsCellEditable to true to enable that particular or cell contains in that row to be able to accept input and overwrite any data which in my case obtained from the Sql database a sort of like input module using tabulation . I am also thinking of using text component or combobox to display the value for user selection , but I do not know how to enable a particular cell for editing if the Jtable created is using a non-editable DefaultModel. If I set the IsCellEditable to true, every single cell would be enable for editing , and this defeat the purpose of enable user input only upon double mouseclicks.
By the way , I am interested to know how to track the data changes in the cell within the jtable so that only those have been modified are notify from the Table model and updated into the Sql table
Could anyone of you out there provide some hints please
Thanks

Hello,
Tablemodellistener could detect the changes in the data, how about the backend database updating and transactional activity that must be associated with the data changes?
What is on my mind is that , the moment there is changes in the data detected by the TableModellistener, whatever records associated with or brougt up by Jtable would be all deleted from the database and then follow by the new set of new records to be inserted into the database. The disadvantage of this method is that everytime the backend database connection and activity need to be executed the moment there is a change in the data in the jtable cell. For example the user may be just amendment to only one cell , but all the records associated need to be deleted and then inserted again.
Perhaps there are better solution to deal with Jtable and JDBC backend connection where in this case, I am using JDO to undertake the database activity like the observable modelling .
Could someone provide the hint please
Thank

Can not show the JCheckBox in JTable cell

I want to place a JCheckBox in one JTable cell, i do as below:
i want the column "d" be a check box which indicates "true" or "false".
String[] columnNames = {"a","b","c","d"};
Object[][] rowData = {{"", "", "", Boolean.FALSE}};
tableModel = new DefaultTableModel(rowData, columnNames);
dataTable = new JTable(tableModel);
dataTable.getColumnModel().getColumn(3).setCellEditor(new DefaultCellEditor(new JCheckBox()));
But when i run it, the "d" column show the string "false" or "true", not the check box i wanted.
I do not understand it, can you help me?
Thank you very much!
coral9527

Do not use DefaultTableModel, create your own table model and you should implement the method
getColumnClass to display the boolean as checkbox ...
I hope the following colde snippet helps you :
class MyModel extends AbstractTableModel {
          private String[] columnNames = {"c1",
"c2"};
public Object[][] data ={{Boolean.valueOf(true),"c1d1"}};
     public int getColumnCount() {
     //System.out.println("Calling getColumnCount");
     return columnNames.length;
public int getRowCount() {
//System.out.println("Calling row count");
return data.length;
public String getColumnName(int col) {
return columnNames[col];
public Object getValueAt(int row, int col) {
return data[row][col];
* JTable uses this method to determine the default renderer/
* editor for each cell. If we didn't implement this method,
* then the last column would contain text ("true"/"false"),
* rather than a check box.
public Class getColumnClass(int c) {
return getValueAt(0, c).getClass();
* Don't need to implement this method unless your table's
* editable.
public boolean isCellEditable(int row, int col) {
//Note that the data/cell address is constant,
//no matter where the cell appears onscreen.
return true;
* Don't need to implement this method unless your table's
* data can change.
public void setValueAt(Object value, int row, int col) {
data[row][col] = value;
fireTableCellUpdated(row, col);

Updating value in a jtable cell

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