minor java.util.TreeMap bug

[Archie Cobbs]

Timothy Stack writes:
> I don't know if this is a real bug or not, but in java.util.TreeMap
> there's this line in deleteNode:
> 
> 325:			x.parent = y.parent;
> 
> The problem is that x can be NIL which is a global variable, which seems
> bad.  One might think a quick fix would be to test for NIL and not set the
> parent, but this causes more grief because the other functions reference
> parent without checking if its non-nil.  Probably not a big problem, just
> thought i'd let you know.

I think this is OK because NIL.parent is never actually used.

I haven't verified this rigourously but it makes sense if you
think about it, because NIL is the child of all leaf nodes, so
NIL has many actual parents.

-Archie

___________________________________________________________________________
Archie Cobbs   *   Whistle Communications, Inc.  *   http://www.whistle.com