A DESCRIPTION OF THE PROBLEM :
The Swing tutorial for using tables includes a section on sorting (http://java.sun.com/docs/books/tutorial/uiswing/components/table.html#sorting) which points to TableSorter.java. This class contains the following nested class:

    private class SortableHeaderRenderer implements TableCellRenderer {
        private TableCellRenderer tableCellRenderer;

        public SortableHeaderRenderer(TableCellRenderer tableCellRenderer) {
            this.tableCellRenderer = tableCellRenderer;
        }

        public Component getTableCellRendererComponent(JTable table,
                                                       Object value,
                                                       boolean isSelected,
                                                       boolean hasFocus,
                                                       int row,
                                                       int column) {
            Component c = tableCellRenderer.getTableCellRendererComponent(table,
                    value, isSelected, hasFocus, row, column);
            if (c instanceof JLabel) {
                JLabel l = (JLabel) c;
                l.setHorizontalTextPosition(JLabel.LEFT);
                int modelColumn = table.convertColumnIndexToModel(column);
                l.setIcon(getHeaderRendererIcon(modelColumn, l.getFont().getSize()));
            }
            return c;
        }
    }


The problem is that in this statement,

    int modelColumn = table.convertColumnIndexToModel(column);

table may be null, as specified in the TableCellRenderer interface documentation for the getTableCellRendererComponent() method:

    table - the JTable that is asking the renderer to draw; can be null

This isn't just theoretical. Another example in the tutorial (http://java.sun.com/docs/books/tutorial/uiswing/components/example-1dot4/TableRenderDemo.java)
does just this inside initColumnSizes():

    comp = headerRenderer.getTableCellRendererComponent(
                                 null, column.getHeaderValue(),
                                 false, false, 0, 0);
    headerWidth = comp.getPreferredSize().width;


I realize Mustang will provide a TableRowSorter class to be used in place of code like TableSorter.java, but maybe this example can still be fixed.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Code that doesn't produce a NullPointerException.
ACTUAL -
Code that produces a NullPointerException.

URL OF FAULTY DOCUMENTATION :
http://java.sun.com/docs/books/tutorial/uiswing/components/example-1dot4/TableSorter.java