<Swing Dev> RFR JDK-6709913: BasicComboBoxUI.isPopupVisible returns NullPointerException

[Sergey Bylokhov]

Hi, Prasanta.

I suggest making the change in the isPopupVisible shorter:

     return popup != null && popup.isVisible();

On 29.07.2020 23:18, Prasanta Sadhukhan wrote:
> Hi All,
> 
> Please review a fix for an issue whereby javax.swing.plaf.basic.BasicComboBoxUI.isPopupVisible returns NullPointerException when called from a overridden method of getModel().
> 
> If a class extends JComboBox and overrides getModel() and then it calls isPopupVisible() from the overriden getModel() it gets NullPointerException the first time.
> 
> Because the popup variable in javax.swing.plaf.basic.BasicComboBoxUI is not set yet.
> 
> Proposed fix is to guard against it by doing a null check for the methods which can be overriden from JComboBox to access "popup" variable.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-6709913
> 
> webrev: http://cr.openjdk.java.net/~psadhukhan/6709913/webrev.0/
> 
> Regards
> Prasanta


-- 
Best regards, Sergey.