JDK 19 enters Rampdown Phase One next week

[mark.reinhold at oracle.com]

JDK 19 enters Rampdown Phase One next week on Thursday, 9 June.
Changes intended for JDK 19 should be in the main-line repository
(https://github.com/openjdk/jdk) by 15:00 UTC on that day [1].

At that time we’ll fork the main line to the JDK 19 stabilization
repository, jdk19, and promote next week’s build and all remaining
JDK 19 builds from there.

We’ll semi-automatically merge changes pushed to jdk19 into the
main-line repository, as we have in previous feature-release
transitions.  This means that:

  - If you make a change in JDK 19 then you needn’t do any extra
    work to get it into the main line, though if a merge conflict
    arises then you might be asked to help resolve it.

  - If you need to make a change in both JDK 19 and the main line
    then just push it to JDK 19, and wait for the automatic merge
    to complete.

Changes pushed to the main line after 15:00 UTC next Thursday will
be bound for JDK 20 only, unless they’re subsequently back-ported
to JDK 19.

The Rampdown Phase One process is defined in JEP 3 [2].

To answer a potential FAQ, again: Now that we’ve moved over to Git,
why don’t we just use a branch in the main-line repository for JDK
19 stabilization work?  A few of us have given that some thought,
but a change of that scope requires a fair amount of preparation
and coordination.  We hope to revisit that option for JDK 20.

- Mark


[1] https://time.is/1500_9_June_2022_in_UTC/Stockholm/London/Boston/San_Francisco?JDK_19_Rampdown_Phase_One
[2] https://openjdk.java.net/jeps/3