Java setting data to JTable from database error

Question

when i try to show data from my database in table this way:

    void AddOrderToTable(JTable projectTable) throws SQLException
{
    zadanie=connect.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_UPDATABLE);
    sql="SELECT * FROM Orders ;";
    dane=zadanie.executeQuery(sql);
    int n=0;
    while (dane.next())
    {
    uzsakNr=dane.getString("Uzsakymo_nr");
    if (uzsakNr != null) {uzsakNr = uzsakNr.trim();}
    priemDat=dane.getString("Priemimo_data");
    if (priemDat != null) {priemDat = priemDat.trim();}
    irengPav=dane.getString("Irenginio_pavadinimas");
    if (irengPav != null) {irengPav = irengPav.trim();}
    model=dane.getString("Modelis");
    if (model != null) {model = model.trim();}
    tip=dane.getString("Tipas");
    if (tip != null) {tip = tip.trim();}
    serial=dane.getString("Serijinis_nr");
    if (serial != null) {serial = serial.trim();}
    priedai=dane.getString("Priedai");
    if (priedai != null) {priedai = priedai.trim();}
    giedAprasy=dane.getString("Gedimo_aprasymas");
    if (giedAprasy != null) {giedAprasy = giedAprasy.trim();}
    status=dane.getString("Statusas");
    if (status != null) {status = status.trim();}
    grazDat=dane.getString("Grazinimo_data");
    if (grazDat != null) {grazDat = grazDat.trim();}
    pastabos=dane.getString("Pastabos");
    if (pastabos != null) {pastabos = pastabos.trim();}
    prieme=dane.getString("Prieme");
    if (prieme != null) {prieme = prieme.trim();}
    clientId=dane.getString("ClientId");
    if (clientId != null) { clientId =  clientId.trim();}


    projectTable.setValueAt(uzsakNr, n, 0);
    projectTable.setValueAt(priemDat, n, 1);
    projectTable.setValueAt(irengPav, n, 2);
    projectTable.setValueAt(model, n, 3);
    projectTable.setValueAt(status, n, 4);
    projectTable.setValueAt(clientId, n, 5);
    n++;
    }
    zadanie.close();
}

i get error

Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 0 >= 0
at java.util.Vector.elementAt(Vector.java:432)
at javax.swing.table.DefaultTableColumnModel.getColumn(DefaultTableColumnModel.java:276)
at javax.swing.JTable.convertColumnIndexToModel(JTable.java:1812)
at javax.swing.JTable.setValueAt(JTable.java:1926)
at GetFromDb.AddOrderToTable(GetFromDb.java:195)
at Remontas.newItemMenuItem_2_actionPerformed(Remontas.java:754)
at Remontas$NewItemMenuItem_2ActionListener.actionPerformed(Remontas.java:710)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1849)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2169)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258)
at javax.swing.AbstractButton.doClick(AbstractButton.java:302)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1051)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1092)
at java.awt.Component.processMouseEvent(Component.java:5517)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3135)
at java.awt.Component.processEvent(Component.java:5282)
at java.awt.Container.processEvent(Container.java:1966)
at java.awt.Component.dispatchEventImpl(Component.java:3984)
at java.awt.Container.dispatchEventImpl(Container.java:2024)
at java.awt.Component.dispatchEvent(Component.java:3819)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3892)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822)
at java.awt.Container.dispatchEventImpl(Container.java:2010)
at java.awt.Window.dispatchEventImpl(Window.java:1791)
at java.awt.Component.dispatchEvent(Component.java:3819)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)

where is problem?

Answer 1

Problem is that the table model is trying to display before you've got any data. If the source data isn't loaded yet, you need to handle that condition rather than attempting to access the objects that are still null.

Answer 2

请注意， ResultSet列的编号为1，而JTable列的编号为0。