FULL PRODUCT VERSION :
java version "1.6.0_07"
Java(TM) SE Runtime Environment (build 1.6.0_07-b06)
Java HotSpot(TM) Client VM (build 10.0-b23, mixed mode, sharing)



ADDITIONAL OS VERSION INFORMATION :
Linux D31004219 2.6.24-19-generic #1 SMP Wed Jun 18 14:43:41 UTC 2008 i686 GNU/Linux


A DESCRIPTION OF THE PROBLEM :
The left arrow of a JTree behaves differently compared jdk1.5 with jdk1.6.

In jdk1.5 I can walk the tree with the RIGHT arrow tree:
- It always select the first child.
- If the node doesn't have any children than the next child of the node's parent is chosen.

In jdk1.6:
- It always selects the first child.
- If the node doesn't have any children than the same node stays selected.

I looked in the sourcecode and indeed there is a difference:
In jdk1.5 the code is:

                       if(!ui.isLeaf(minSelIndex) &&
                           !tree.isExpanded(minSelIndex)) {
                            ui.toggleExpandState(ui.getPathForRow
                                              (tree, minSelIndex));
                            newIndex = -1;
                        }
                        else
                            newIndex = Math.min(minSelIndex + 1, rowCount - 1);

In jdk1.6 the code is:
                        if (!ui.isLeaf(minSelIndex)) {
                            if (!tree.isExpanded(minSelIndex)) {
                                ui.toggleExpandState(minSelPath);
                            }
                            else if (childCount > 0) {
                                newIndex = Math.min(minSelIndex + 1, rowCount - 1);
                            }
                        }



STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
You can just try the SwingSet2 demo in jdk1.5 and jdk 1.6.

- Select the Tree demo.
- Select the first node.
- Keep pressing the RIGHT ARROW key.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The expected result is that you can traverse the whole tree with the RIGHT ARROW key.
So at the end the last node is selected.
ACTUAL -
In jdk1.5 the tree is traversed and the last node is selected.
In jdk1.6 the tree stops traversing when the first leaf of the tree is selected.

REPRODUCIBILITY :
This bug can be reproduced always.

Release Regression From : 6
The above release value was the last known release where this
bug was not reproducible. Since then there has been a regression.