Another JTable/buttons in cells query - event forwarding

Question

Hi Everyone.
Apologies in advance for yet another thread on this subject. I realise this has been discussed a number of times but I can't find what seems like a definitive solution.
I understand what the fundamental issue is with putting JComponents in table cells - i.e. that the cells are rendered essentially as static visual entities, that they're not "components" as such and will not receive events.
I'd like to implement JButtons in table cells so that they behave as "normally" as possible - i.e. handle their own roll-over appearance, handle their own pressed appearance, and fire action events when pressed, with as little manual intervention in these mechanisms (e.g. in mouse listener code) as possible. I'm trying to do this by forwarding mouse events from the table to the button, but this doesn't seem to work as I'd hoped and I have various questions...
(Background: I have implemented JButton objects in the data model, and the getTableCellRendererComponent() method returns *(JButton)value*.)
My first question concerns the interception of mouse events. The usual technique would be to add a mouse listener and/or mouse motion listener to the table, and implement mouseClicked(), mousePressed() etc. However, can I override the table's processMouseEvent() and processMouseMotionEvent() methods instead, and from here forward events to buttons where appropriate, or process normally with super.processMouseEvent()? My motivation for doing this would be specifically not to invoke the super methods where events were forwarded to buttons - effectively consuming the event. Is this correct technique?
My second question concerns attempts to reproduce button roll-over appearances. The JTable is of course considered a single entity as far as mouse events are concerned, and MOUSE_ENTERED and MOUSE_EXITED events aren't generated as the pointer moves from cell to cell. Merely forwarding mouse events to buttons - which will mostly be MOUSE_MOVED events - seems to be insufficient and presumably the roll-over appearance change relies upon ENTERED and EXITED events occurring at the proper times.
I mimicked this behaviour in my override of processMouseMotionEvent() by calculating the value (i.e. JButton reference) of the cell under the mouse pointer, and if it wasn't the same as for the previous event, manually creating a MOUSE_ENTERED event and forwarding it to the new button. This seemed to work - the rollovers were happening (provided a table repaint() was performed), but it seemed to work without needing to explicitly sending a MOUSE_EXITED to the previous button before sending MOUSE_ENTERED to the new. I'm unclear why this is so - I was half-expecting both buttons to acquire the roll-over state, and they didn't.
Also, I had assumed that having taken care of this, I should forward MOUSE_MOVED events occurring within the confines of a cell's area to the button verbatim, but this seems to instantly cancel out any roll-over (visually the button would briefly flash a roll-over appearance as the pointer moved into its cell bounds). Why might this be so?
My last question is about the actual pressing of the button. I had hoped that forwarding MOUSE_CLICKED, MOUSE_PRESSED and MOUSE_RELEASED would cause the button to (a) acquire the button-pressed state, and (b) fire an action event to its action listeners. Neither of these things occur, and I don't understand why not.
In summary, is interception and forwarding of events like this a viable technique for implementing table cell buttons? The various solutions that a Google trawl throws up all reproduce button-pressing mechanics in varying degrees, some just detecting a click and calling some user function, others manually manipulating the button model in the mouse handler etc. If possible I'd like to avoid this, and leave as much processing as possible to the button's native code.
Thanks in advance for any suggestions received.
Regards,
A.

Answer 1

try to look on this
http://java.sun.com/docs/books/tutorial/uiswing/components/table.html#editrender