From 97ed0a93bb75d0f920c976527f4f5fc0b6065beb Mon Sep 17 00:00:00 2001
From: shainaraskas <58563081+shainaraskas@users.noreply.github.com>
Date: Thu, 24 Oct 2024 13:26:15 -0400
Subject: [PATCH] Make a minor change to trigger release note process (#113975)

* changelog entry
---
 docs/changelog/113975.yaml                    | 19 +++++++++++++++++++
 docs/reference/mapping/params/format.asciidoc |  4 ++--
 2 files changed, 21 insertions(+), 2 deletions(-)
 create mode 100644 docs/changelog/113975.yaml

diff --git a/docs/changelog/113975.yaml b/docs/changelog/113975.yaml
new file mode 100644
index 0000000000000..632ba038271bb
--- /dev/null
+++ b/docs/changelog/113975.yaml
@@ -0,0 +1,19 @@
+pr: 113975
+summary: JDK locale database change
+area: Mapping
+type: breaking
+issues: []
+breaking:
+  title: JDK locale database change
+  area: Mapping
+  details: |
+    {es} 8.16 changes the version of the JDK that is included from version 22 to version 23. This changes the locale database that is used by Elasticsearch from the COMPAT database to the CLDR database. This change can cause significant differences to the textual date formats accepted by Elasticsearch, and to calculated week-dates.
+
+    If you run {es} 8.16 on JDK version 22 or below, it will use the COMPAT locale database to match the behavior of 8.15. However, starting with {es} 9.0, {es} will use the CLDR database regardless of JDK version it is run on.
+  impact: |
+    This affects you if you use custom date formats using textual or week-date field specifiers. If you use date fields or calculated week-dates that change between the COMPAT and CLDR databases, then this change will cause Elasticsearch to reject previously valid date fields as invalid data. You might need to modify your ingest or output integration code to account for the differences between these two JDK versions.
+
+    Starting in version 8.15.2, Elasticsearch will log deprecation warnings if you are using date format specifiers that might change on upgrading to JDK 23. These warnings are visible in Kibana.
+
+    For detailed guidance, refer to <<custom-date-format-locales,Differences in locale information between JDK versions>> and the https://ela.st/jdk-23-locales[Elastic blog].
+  notable: true
diff --git a/docs/reference/mapping/params/format.asciidoc b/docs/reference/mapping/params/format.asciidoc
index 943e8fb879ff3..6c82b04eb5fe5 100644
--- a/docs/reference/mapping/params/format.asciidoc
+++ b/docs/reference/mapping/params/format.asciidoc
@@ -34,13 +34,13 @@ down to the nearest day.
 Completely customizable date formats are supported. The syntax for these is explained in
 https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/time/format/DateTimeFormatter.html[DateTimeFormatter docs].
 
-Note that whilst the built-in formats for week dates use the ISO definition of weekyears,
+Note that while the built-in formats for week dates use the ISO definition of weekyears,
 custom formatters using the `Y`, `W`, or `w` field specifiers use the JDK locale definition
 of weekyears. This can result in different values between the built-in formats and custom formats
 for week dates.
 
 [[built-in-date-formats]]
-==== Built In Formats
+==== Built-in formats
 
 Most of the below formats have a `strict` companion format, which means that
 year, month and day parts of the month must use respectively 4, 2 and 2 digits