TableSorter

[mattj]

Im using TableSorter.java available from java.sun.com/docs/books/tutorial/uiswing/examples/components/TableSorterDemoProject/src/components/TableSorter.java
to sort my table, which includes a column with dates. Heres what i tried

DefaultTableModel model = new DefaultTableModel() {
            Class [] classes = {int.class, String.class, String.class, Date.class, Date.class, double.class};
                
            public Class getColumnClass(int column) {
                return classes[column];
            }
        };
		
	
        TableSorter sorter = new TableSorter(model);
	JTable table = new JTable(sorter);
	sorter.setTableHeader(table.getTableHeader());

However when i modify my table in any way it comes up with a NullPointerException. If i just use the DefaultTableModel my code works fine except it compares everything as strings.

How do i compare the table elements using the correct class?

[Norm]

it comes up with a NullPointerException.

If you are getting an error, copy and paste the full text of the message here. The error message has the souce code line number in it. Copy and paste the code around that line here also.

[mattj]

No line number was given, if i replace

DefaultTableModel model = new DefaultTableModel() {
            Class [] classes = {int.class, String.class, String.class, Date.class, Date.class, double.class};
                
            public Class getColumnClass(int column) {
                return classes[column];
            }
        };

with

DefaultTableModel model =new DefaultTableModel();

The program works fine. Here is the exception.

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at javax.swing.JTable.prepareRenderer(Unknown Source)
at javax.swing.plaf.basic.BasicTableUI.paintCell(Unkn own Source)
at javax.swing.plaf.basic.BasicTableUI.paintCells(Unk nown Source)
at javax.swing.plaf.basic.BasicTableUI.paint(Unknown Source)
at javax.swing.plaf.ComponentUI.update(Unknown Source)
at javax.swing.JComponent.paintComponent(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.paintToOffscreen(Unknown Source)
at javax.swing.BufferStrategyPaintManager.paint(Unkno wn Source)
at javax.swing.RepaintManager.paint(Unknown Source)
at javax.swing.JComponent._paintImmediately(Unknown Source)
at javax.swing.JComponent.paintImmediately(Unknown Source)
at javax.swing.RepaintManager.paintDirtyRegions(Unkno wn Source)
at javax.swing.RepaintManager.paintDirtyRegions(Unkno wn Source)
at javax.swing.RepaintManager.seqPaintDirtyRegions(Un known Source)
at javax.swing.SystemEventQueueUtilities$ComponentWor kRequest.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilter s(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(U nknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarch y(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)

[hardwired]

I was able to get the same exception by using int.class in a test app.
Changing it to Integer.class worked okay.
Apparently, autoboxing doesn't work here.

Class[] classes = {Integer.class, String.class, String.class,
                   Date.class, Date.class, Double.class};