RFR: 8364146: JList getScrollableUnitIncrement return 0 [v8]

[Phil Race]

On Tue, 11 Nov 2025 11:55:59 GMT, Prasanta Sadhukhan <psadhukhan at openjdk.org> wrote:

>> It seems JList.getScrollableUnitIncrement can sometime return 0 instead of positive number which is not specified in the javadoc which can lead to confusion. Clarified javadoc as to when it can return 0.
>
> Prasanta Sadhukhan has updated the pull request incrementally with one additional commit since the last revision:
> 
>   spec wording

src/java.desktop/share/classes/javax/swing/JList.java line 2510:

> 2508:      * @param direction less or equal to zero to scroll up/back,
> 2509:      *                  greater than zero for down/forward
> 2510:      * @return the non-negative "unit" increment value

Since zero isn't "the distance to scroll to the next row", we need to explain when and why it can be zero.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/26500#discussion_r2566005916