In the tutorial on http://download.oracle.com/javase/tutorial/uiswing/events/propertychangelistener.html
following chunk of code has error:

KeyboardFocusManager focusManager =
   KeyboardFocusManager.getCurrentKeyboardFocusManager();
focusManager.addPropertyChangeListener(new FocusManagerListener());
...
public FocusManagerListener() implements PropertyChangeListener {
    public void propertyChange(PropertyChangeEvent e) {
        String propertyName = e.getPropertyName();
        if ("focusOwner".equals(propertyName) {
            ...
        } else if ("focusedWindow".equals(propertyName) {
            ...
        }
    }
    ...
}

The line:
"public FocusManagerListener() implements PropertyChangeListener {"
should look like:
"public FocusManagerListener implements PropertyChangeListener {"