<Swing Dev> [10] RFR: 8182577: Crash when Tab key moves focus to a JCheckbox with a custom ButtonModel

[Semyon Sadetsky]

Hi Prasanta,

With the DefaultButtonModel we can get the same exception if a custom 
implementation of the ButtonModel is used.

So, it is better check whether  the model is a DefaultButtonModel and 
skip if grouping is not supported. Or, perhaps, it is reasonable to pull 
up the getGroup() into the ButtonModel interface which already has 
setGroup().

--Semyon


On 06/20/2017 10:21 AM, Prasanta Sadhukhan wrote:
> Hi All,
>
> Please review a fix for an issue where a crash is reported when focus 
> is moved with custom ButtonModel.
> Issue was in LayoutFocusTraversalPolicy, the ButtonModel was wrongly 
> typecasted to JToggleButton when the button model is 
> DefaultButtonModel, resulting in ClassCastException.
>
> Proposed fix is to cast to super class DefaultButtonModel and then 
> check for JToggleButton member.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8182577
> webrev: http://cr.openjdk.java.net/~psadhukhan/8182577/webrev.00/
>
> Regards
> Prasanta