Reporting errors while filling a JTable

Question

Hello all, this is my first post here.
When i implement a class derived from AbstractTableModel to show some data in a JTable, sometimes, specially when this data is coming from databases, i need to be able to report any errors that ocur while geting that data via a message dialog, for example, specifically inside the overriden getValueAt() function, eg.
public Object getValueAt(int rowIndex, int columnIndex) {
try{
..... read the information from the database
}catch(SQLException ex){
JOptionPane.showMessageDialog(null, "Error!"........ show the error
this actually works, the message dialog is shown if an error ocurs, however there are 2 problems:
1.- after the user closes the message dialog, the JTable is not painted properly.
2.- i get all these exceptions:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.SwingUtilities.computeIntersection(SwingUtilities.java:417)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:430)
at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:114)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:461)
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)
If i just remove the line that shows the message dialog, then everything works ok. But i NEED a way to inform the user that something went wrong, how do i do this?
Thanks!

Answer 1

Hey numbnuts,
People keep reporting this error and you keep closing it w/o proper attention:
In SwingUtilities, sometimes "dest" becomes null. Don't tell why - sometimes its because of some library maybe you didnt write. But if you put in a "*if (dest == null) o something ...*" in there - it would fix it. Even a freshman comp sci programmer knows that.
And you wonder why nobody wants to learn Java anymore...
    public static Rectangle computeIntersection(int x,int y,int width,int height,Rectangle dest) {
        int x1 = (x > dest.x) ? x : dest.x;
        int x2 = ((x+width) < (dest.x + dest.width)) ? (x+width) : (dest.x + dest.width);
        int y1 = (y > dest.y) ? y : dest.y;
        int y2 = ((y + height) < (dest.y + dest.height) ? (y+height) : (dest.y + dest.height));
        dest.x = x1;
        dest.y = y1;
        dest.width = x2 - x1;
        dest.height = y2 - y1;
     // If rectangles don't intersect, return zero'd intersection.
     if (dest.width < 0 || dest.height < 0) {
         dest.x = dest.y = dest.width = dest.height = 0;
        return dest;
    }End Communication