I have JScrollPane , which contains few AWT & Swing Components. I resize the frame , so that i can see the scrollbars of JScrollPane. I resize the frame such that AWT Choice can be seen 1 or 2 pixel gap between the JScrollPane's vertical bar or choice is seen on the JScrollPane's vertical bar. I click on the choice so that i can select the item of the choice. Once the choice popup is open. Try pressing the down arrow key. Observe that JScrollPane's vertical scrollbar tumb is moving , this is an another issue. Once the JScrollPane's vertical scrollbar tumb touchs the downarrow . Press Left arrow key . Now I can see that choice disappears , only popup is seen. But the choice location or position is changed, i,e choice is added below the JScrollPane horizontal scrollbar. I have attached the screen shot.

I can three issues here
1) JScrollPane takes the event , while tring to navigate the choice.
2) Choice & other components disappears.
3) Choice changes its position.

I tested this with 6u12 b02 promoted build.

Step to Reproduced:-
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1) Run the attached program.
2) Resize the frame such that AWT Choice can be seen 1 or 2 pixel gap between the JScrollPane's vertical bar or choice is seen on the JScrollPane's vertical bar.
3) Click on the choice, to see the choice's popup menu.
4) Press down arrow to navigate the choice's popup. Observe that JScrollPane's vertical scrollbar tumb is moving. Once the tumb touches vertical scrollbar down arrow button. stop navigating.
Note : Observe that choice gets disappear.
5) Press left arrow button 3 to 4 times. Press escape key, so that choice popup gets closed.
6) Observe that choice is place below the the JScrollPane horizontal scrollbar.


http://monaco.sfbay.sun.com/detail.jsf?cr=6783180 is a related bug.