{
DefaultTableColumnModel m1 = new DefaultTableColumnModel();
TableColumnModelListener[] listeners = m1.getColumnModelListeners();
harness.check(listeners.length, 0);
TableColumnModelListener listener = new MyListener();
m1.addColumnModelListener(listener);
listeners = m1.getColumnModelListeners();
harness.check(listeners[0], listener);
TableColumnModelListener listener2 = new MyListener();
m1.addColumnModelListener(listener2);
listeners = m1.getColumnModelListeners();
// convert to a list, because the spec doesn't say anything about the
// order of the listeners
List list = Arrays.asList(listeners);