JTable checkboxes doesn't retain their selection when a new row is added!!

Question

HI,
My gui has the JTable component which has 5 columns. out of which 4 columns are checkboxes. whenever i select an item from the Jlist and click on the add button it will add a new row in JTable.
but the problem is whenever a new row is added to the table. the previously selected checkboxes of previous rows are being deselected. But i want to retain the selection of my previous rows even when a new row is added. please help me how to achieve this..i am posting my JTable code here:
class FunctionTableModel extends AbstractTableModel{
       /** The instances who's attribute structure we are reporting */
    //protected InitModel m_init;
    protected String func_element;
    protected int counter;
    //protected String[] func_array;
    protected Vector func_vector;
    /** The flag for whether the instance will be included */
    protected boolean [] m_Sum;
    protected boolean [] m_Min;
    protected boolean [] m_Avg;
    protected boolean [] m_Max;
    protected boolean [] m_SD;
     * Creates the tablemodel with the given set of instances.
     * @param instances the initial set of Instances
    public FunctionTableModel() {
      counter =0;
         func_vector = new Vector();
     public FunctionTableModel(Vector vec) {
        func_vector = vec;
    public Vector getDataVector(){
        return func_vector;
     * Sets the tablemodel to look at a new set of instances.
     * @param instances the new set of Instances.
    public void setElement(Vector vec) {
           for(int i=0;i<vec.size();i++){
        func_vector.add(vec.elementAt(i));
        counter++;
      fireTableDataChanged();   
      m_Sum = new boolean [counter];
      m_Min = new boolean[counter];
      m_Avg = new boolean[counter];
      m_Max = new boolean[counter];
      m_SD = new boolean[counter];
     * Gets the number of attributes.
     * @return the number of attributes.
    public int getRowCount() {
           return func_vector.size();
     * Gets the number of columns: 3
     * @return 3
    public int getColumnCount() {
      return 6;
     * Gets a table cell
     * @param row the row index
     * @param column the column index
     * @return the value at row, column
    public Object getValueAt(int row, int column) {
      switch (column) {
      case 0:
        return func_vector.elementAt(row);
      case 1:
        return new Boolean(m_Sum[row]);
      case 2:
        return new Boolean(m_Min[row]);
      case 3:
        return new Boolean(m_Avg[row]);
      case 4:
        return new Boolean(m_Max[row]);
      case 5:
        return new Boolean(m_SD[row]); 
      default:
        return null;
    public void removeAll(){
        func_vector.removeAllElements();
        fireTableDataChanged();
     * Gets the name for a column.
     * @param column the column index.
     * @return the name of the column.
    public String getColumnName(int column) {
      switch (column) {
      case 0:
        return new String("Function Selected");
      case 1:
        return new String("Sum");
      case 2:
        return new String("Min");
      case 3:
        return new String("Avg");
      case 4:
        return new String("Max");
      case 5:
        return new String("SD");   
      default:
     return null;
     * Sets the value at a cell.
     * @param value the new value.
     * @param row the row index.
     * @param col the column index.
    public void setValueAt(Object value, int row, int col) {
      if(col == 0){
        counter++;
        func_vector.add(counter,value.toString());
      if (col == 1)
        m_Sum[row] = ((Boolean) value).booleanValue();
      if (col == 2)
        m_Min[row] = ((Boolean) value).booleanValue();
      if (col == 3)
        m_Avg[row] = ((Boolean) value).booleanValue();
      if (col == 4)
        m_Max[row] = ((Boolean) value).booleanValue();
      if (col == 5)
        m_SD[row] = ((Boolean) value).booleanValue();       
     * Gets the class of elements in a column.
     * @param col the column index.
     * @return the class of elements in the column.
    public Class getColumnClass(int col) {
         return getValueAt(0, col).getClass();
     * Returns true if the column is the "selected" column.
     * @param row ignored
     * @param col the column index.
     * @return true if col == 1.
    public boolean isCellEditable(int row, int col) {
      if (col >= 1) {
         return true;
      return false;
    public void removeRow(int row){
        if(row<=func_vector.size()){
                      func_vector.removeElementAt(row);
            counter--;
        fireTableDataChanged();
    }

Answer 1

hi parvathi,
i have made changes to my previous code and here's the code:
  class FunctionTableModel extends DefaultTableModel{
       /** The instances who's attribute structure we are reporting */
    //protected InitModel m_init;
    protected String func_element;
    protected int counter;
    protected int counter1;
    //protected String[] func_array;
    protected Vector func_vector;
    /** The flag for whether the instance will be included */
    protected boolean [] m_Sum;
    protected boolean [] m_Min;
    protected boolean [] m_Avg;
    protected boolean [] m_Max;
    protected boolean [] m_SD;
    //protected Vector m_Sum1;
    //protected Vector m_Min1;
    //protected Vector m_Avg1;
    //protected Vector m_Max1;
    //protected Vector m_SD1;
     * Creates the tablemodel with the given set of instances.
     * @param instances the initial set of Instances
    public FunctionTableModel() {
        System.out.println("entered the constr");
      counter =0;
      //counter1=0;
      //m_Sum1 = new Vector();
      //m_Min1 = new Vector();
      //m_Avg1 = new Vector();
      //m_Max1 = new Vector();
      //m_SD1 = new Vector();
      //func_array = new String[];
      func_vector = new Vector();
     public FunctionTableModel(Vector vec) {
        func_vector = vec;
        //setElement(func_vector);
    public Vector getDataVector(){
        return func_vector;
     * Sets the tablemodel to look at a new set of instances.
     * @param instances the new set of Instances.
    public void addRow(Vector vec) {
      //counter++; 
      //func_element = ele;
      //System.out.println("FunctionTableModel- setElement() method");
      for(int i=0;i<vec.size();i++){
        func_vector.add(vec.elementAt(i));
        counter++;  
       //System.out.println("counter ="+counter+new boolean[counter]); 
        //m_Sum1 = m_Sum;
        //m_Min1 = m_Min;
        //m_Avg1 = m_Avg;
        //m_Max1 = m_Max;
        //m_SD1 = m_SD;
        //m_Sum = new boolean[counter];
        //System.out.println("at setElement");
        m_Sum = new boolean[counter];
        //System.out.println(counter);
        m_Min = new boolean[counter];
        //m_Min;
        m_Avg = new boolean[counter];
        //m_Avg1 = m_Avg;
        m_Max = new boolean[counter];
        //m_Max1 = m_Max;
        m_SD = new boolean[counter];
        //m_SD1 = m_SD;
        //counter1++;
      //func_array[counter]=ele;
      //func_vector.add(counter,ele);
      fireTableDataChanged();  
     * Gets the number of attributes.
     * @return the number of attributes.
    //public int getRowCount() {
      //System.out.println("FunctionTableModel- getRowCount() method");
      //return func_vector.size();
     * Gets the number of columns: 3
     * @return 3
    public int getColumnCount() {
      return 6;
     * Gets a table cell
     * @param row the row index
     * @param column the column index
     * @return the value at row, column
    public Object getValueAt(int row, int column) {
      switch (column) {
      case 0:
        return func_vector.elementAt(row);
      case 1:{
        //System.out.println("in case 1");
        //Boolean m_Sum_Value = new Boolean(m_Sum[row]);
        //System.out.println("m_Sum_Value:"+m_Sum_Value.booleanValue());
        return new Boolean(m_Sum[row]);
        //m_Sum1.add(m_Sum_Value);
        //return m_Sum_Value;
      case 2:
        return new Boolean(m_Min[row]);
      case 3:
        return new Boolean(m_Avg[row]);
      case 4:
        return new Boolean(m_Max[row]);
      case 5:
        return new Boolean(m_SD[row]); 
      default:
        return null;
    public void removeAll(){
        func_vector.removeAllElements();
        //m_Sum1.removeAllElements();
        fireTableDataChanged();
     * Gets the name for a column.
     * @param column the column index.
     * @return the name of the column.
    public String getColumnName(int column) {
      switch (column) {
      case 0:
        return new String("Function Selected");
      case 1:
        return new String("Sum");
      case 2:
        return new String("Min");
      case 3:
        return new String("Avg");
      case 4:
        return new String("Max");
      case 5:
        return new String("SD");   
      default:
     return null;
     * Sets the value at a cell.
     * @param value the new value.
     * @param row the row index.
     * @param col the column index.
    public void setValueAt(Object value, int row, int col) {
      if(col == 0){
        counter++;
        func_vector.add(counter,value.toString());
      if (col == 1) {
        m_Sum[row] = ((Boolean) value).booleanValue();
        //System.out.println("m_Sum length "+m_Sum.length);
        //for(int i=0;i<=row;i++)
        //    System.out.println("m_Sum1 "+i+((Boolean)m_Sum1.elementAt(i)).booleanValue());
        //System.out.println("m_Sum1["+row+"] "+ ((Boolean)m_Sum1.elementAt(row)).booleanValue());
        //    System.out.println("m_Sum["+i+"] "+ m_Sum);
if (col == 2)
m_Min[row] = ((Boolean) value).booleanValue();
if (col == 3)
m_Avg[row] = ((Boolean) value).booleanValue();
if (col == 4)
m_Max[row] = ((Boolean) value).booleanValue();
if (col == 5)
m_SD[row] = ((Boolean) value).booleanValue();
* Gets the class of elements in a column.
* @param col the column index.
* @return the class of elements in the column.
public Class getColumnClass(int col) {
return getValueAt(0, col).getClass();
* Returns true if the column is the "selected" column.
* @param row ignored
* @param col the column index.
* @return true if col == 1.
public boolean isCellEditable(int row, int col) {
if (col >= 1) {
     return true;
return false;
public void removeRow(int row){
if(row<=func_vector.size()){
func_vector.removeElementAt(row);
counter--;
fireTableDataChanged();
previouslu i was using the setElement method. now i have replaced with the addRow method...
but anyways...the control is not going to any of these overridden methods...and none of the elements are added to the table. But i comment of all the addRow, getValueAt, getColumnClass methods...then it's adding rows to the table but with only the first column all the remaiing columns are just empty...
i am fed up with this...if you observe i have commented out somany lines...becoz i am trying to save my boolean array values into a vector..but that was also in vain...
i appreciate for ur help...
thanks
sri