issues after porting a mac app from Java 6 to 7u9

[Rick Hillegas]

I have ported an app from Java 6 to 7u9. I am seeing the following 
behaviors. One behavior is specific. The other is vague and I will need 
to run the app for a while longer before I come up with a theory about 
where the problem may be:

1) Drag-and-drop on a JTable behaves differently. On Java 6, when I drag 
a cell between locations on a JTable, the following happens:

   - A ghost rectangle appears as the drag starts.
   - I drag the ghost rectangle onto the target cell, positioning it so 
that it lines up with the target border, and then release the mouse.
   - My drag-and-drop handler then processes events correctly.

Now on Java 7 the following happens:

   - The ghost rectangle appears as before.
   - But I have to position it differently. Now I have to just barely 
overlap the bottom boundary of the ghost rectangle with the top boundary 
of the target cell in order to generate events for my drag-and-drop handler.

Is this a known difference in behavior?

2) The other problem is probably too vague, but here goes: I seem to 
have memory management issues. After running the app for a while, it 
starts freezing up and I watch the beachball spin. Eventually the app 
becomes unusable and I have to re-start it. Is it expected that I will 
need to give an app more memory in order to run it on Java 7?

Thanks,
-Rick