Can I base all of my windows on JFrame?

[Kaydell Leavitt]

I'm used to a class library (pre-Java, but object-oriented), that based all windows on a single base class. If written in Java, it would be like the following:

public abstract class VWindow extends JFrame implements
WindowListener,
WindowFocusListener,
ActionListener,
Runnable
{ // common functionality is implemented here }
public abstract DatabaseWindow extends VWindow { // common functiionality for DB Windows goes here. }
public InventoryItemWindow extends DatabaseWindow { // concrete implementation }
public VDialog extends JFrame { // All VDialogs are modal. VWindow can be modeless }
public VAlert extends VDialog { // inherits from VDialog and from VWindow and from JFrame }

Is the above design possible in Swing, using the JFrame class? I'd like everything, deep-down to have a common anscestor class like JFrame. I'd rather do this than use three different classes:

JFrame for modeless windows.
JDialog for modal windows.
and
JOptionPane for simple alerts.

Is my design a good use of Swing or am I "going against the grain."

Kaydell
[ May 27, 2007: Message edited by: Kaydell Leavitt ]

[Ernest Friedman-Hill]

All of these classes already have java.awt.Component as an ancestor; maybe you can make use of that fact.

But as far as top level windows go, I don't think there's any reason you're forced to use JDialog or JOptionPane, except for modality; off the top of my head I don't believe you can implement a true modal dialog with JFrame (someone may prove me wrong here, though.) If you can live without true modal dialogs, then there's no reason not to do what you suggest, other than the reinventing-the-wheel that' you'd be doing instead of using JOptionPane.

[Campbell Ritchie]

. . . Go through the API and you will find that JWindow, JDialog and JFrame already inherit from Object in the same fashion.