<Swing Dev> [9] Review request for 8163167: [PIT] javax/swing/JTextArea/ScrollbarFlicker/ScrollFlickerTest.java always fail

[Semyon Sadetsky]

On 8/23/2016 8:35 PM, Sergey Bylokhov wrote:
> On 23.08.16 20:29, Semyon Sadetsky wrote:
>> On 8/23/2016 8:00 PM, Sergey Bylokhov wrote:
>>
>>> Just to clarify, on what L&f the bug is reproduced? Why we call the
>>> listener 6 times when we set the size of scroll only once?
>>> I tried to print the bounds of the viewport in the listener and it
>>> seems that they are the same most of the time:
>>> bounds = java.awt.Rectangle[x=2,y=2,width=15,height=46]
>>> bounds = java.awt.Rectangle[x=2,y=2,width=15,height=46]
>>> bounds = java.awt.Rectangle[x=2,y=2,width=0,height=46]
>>> bounds = java.awt.Rectangle[x=2,y=2,width=0,height=46]
>>> bounds = java.awt.Rectangle[x=2,y=2,width=0,height=46]
>>> bounds = java.awt.Rectangle[x=2,y=2,width=0,height=46]
>>>
>>> So probably it is possible to minimize the number of calls?
>> This is expected behavior. It is because JScrollPane consists of several
>> areas which may report changes each time they got a size.
>
> But in some cases the size is the same, for example in the text above 
> notification occurred twice for [x=2,y=2,width=15,height=46].
This is how the internal JScrollPane layout algorithm works. It is most 
optimal way to layout the viewport, the text inside it along with the 
scroll bars. It requires several iterations usually.
>>>
>>> On 23.08.16 11:59, Alexander Scherbatiy wrote:
>>>> The fix looks good to me.
>>>>
>>>> Thanks,
>>>> Alexandr.
>>>>
>>>> On 23/08/16 11:40, Semyon Sadetsky wrote:
>>>>> Hello,
>>>>>
>>>>> Please review fix for JDK9:
>>>>>
>>>>> bug: https://bugs.openjdk.java.net/browse/JDK-8163167
>>>>>
>>>>> webrev: http://cr.openjdk.java.net/~ssadetsky/8163167/webrev.00/
>>>>>
>>>>> The cause of this test bug is revalidating JScrollPane layout may 
>>>>> take
>>>>> various number of iterations on different L&Fs.
>>>>>
>>>>> To fix the test the counter listener is added after the layout
>>>>> revalidation has been started.
>>>>>
>>>>> --Semyon
>>>>>
>>>>
>>>
>>>
>>
>
>