RFR: JDK-8323760 clarify specification of Map::putIfAbsent return value [v3]

[Stuart Marks]

On Wed, 14 Feb 2024 20:46:17 GMT, John Hendrikx <jhendrikx at openjdk.org> wrote:

>> Update the documentation for `@return` tag of `putIfAbsent` to match the main description. `putIfAbsent` uses the same wording as `put` for its `@return` tag, but that is incorrect.  `putIfAbsent` never returns the **previous** value, as the whole point of the method is not the replace the value if it was present.  As such, if it returns a value, it is the **current** value, and in all other cases it will return `null`.
>
> John Hendrikx has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Use new suggestion and remove original clarification

See CSR comments from Martin Buchholz:

https://bugs.openjdk.org/browse/JDK-8325811?focusedId=14659527&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14659527

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

PR Comment: https://git.openjdk.org/jdk/pull/17438#issuecomment-2021785703