JTableModel

Question

I have a problem with my JTableModel. every time the first query returns no rows, the second query with some values is not able to create a new table model.
If the preceding rows have values, i can run as many queries as possible.
How do i sort this out?
public void getTable(){
      //getting a select statement from a function that generates it from the GUI 
        String whereclause=getCriteria();
        try {
            model=new JTableModelClass(whereclause,columnNames);
            table.setModel(model);
            table.setPreferredScrollableViewportSize(new Dimension(500, 70));
            table.setFillsViewportHeight(true);
            table.setAutoCreateRowSorter(true);
            table.getTableHeader().setReorderingAllowed(true);
            if(scrollPane==null){
                scrollPane = new JScrollPane();
                scrollPane.setViewportView(table);
            } else{
                scrollPane.setViewportView(table);
            scrollPane.setSize(900,400);
            scrollPane.setBounds(0,0,900,400);
            scrollPane.setWheelScrollingEnabled(true);
            scrollPane.createHorizontalScrollBar();
            this.jPanel3.add(scrollPane);
        catch(Exception eta){
            System.out.println("Error in setting a table model :  "+eta.getMessage());
public class JTableModelClass extends AbstractTableModel {
    Object [][] data;
    JTable table;
    Vector vectordata,rowdata;
    String[] columnNames;
    JDataBase db=new JDataBase();
    /** Creates a new instance of JTableModelClass */
    public JTableModelClass(String query, Vector colnames) {
        columnNames=new String[colnames.size()];
        String myquery=query;
        String conn=db.connection.toString();
        vectordata=db.getData(query);
        for(int i=0;i<colnames.size();i++){
            columnNames=(String)colnames.elementAt(i);
System.out.println("get no of rows");
int rows=db.no_rows;
Object row;
data=new Object[rows][columnNames.length];
if(rows==0){
System.out.println("No Such Data Found");
} else{
System.out.println("Some Data Found");
for(int i=0;i<rows;i++){
rowdata=(Vector)vectordata.elementAt(i);
for(int j=0;j<columnNames.length;j++){
data[i][j]=rowdata.elementAt(j);
System.out.println("making a table done");
public int getColumnCount() {
return columnNames.length;
public int getRowCount() {
return data.length;
public String[] getTableHeader(){    
return columnNames;
public void addRow(Object[] row) {
for (int i=0; i<columnNames.length; i++) {
data[data.length+1][i] = row[i];
fireTableRowsUpdated(data.length+1,data.length+1);
public String getColumnName(int col) {
return columnNames[col];
public Object getValueAt(int row, int col) {
return data[row][col];
public Class getColumnClass(int c) {
return getValueAt(0, c).getClass();
public static void main(String[] args) {

Answer 1

Don't multi-post.
My response in your last posting said "In The Future".
Anyway you where given an answer so there was no need to repost.
The DefaultTableModel does extend AbstractTableModel. So you copy your ResultSet to the DefaultTableModel.
Take time to understand the suggestion given to you before cluttering the forums with multiple postings.
hope everyone knows that the Abstract table model needs a rowData [][], which is a 2D arrayNo it doesn't. An AbstractTableModel does not provide any storage of the data which is why you need to implement all the methods yourself.