This code:

java.time.LocalDateTime.parse("4714-11-24 00:00:00 BC", java.time.format.DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss G", Locale.ROOT));

fails to parse after JDK-8306116 (CLDR 44.0 update).

Running the code in jshell before I get:

$ ./jdk-22+23/bin/jshell
| Welcome to JShell -- Version 22-beta
| For an introduction type: /help intro

jshell> java.time.LocalDateTime.parse("4714-11-24 00:00:00 BC", java.time.format.DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss G", Locale.ROOT));
$1 ==> -4713-11-24T00:00

jshell>

After I get:

bin/jshell
| Welcome to JShell -- Version 22-internal
| For an introduction type: /help intro

jshell> java.time.LocalDateTime.parse("4714-11-24 00:00:00 BC", java.time.format.DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss G", Locale.ROOT));
| Exception java.time.format.DateTimeParseException: Text '4714-11-24 00:00:00 BC' could not be parsed at index 20
| at DateTimeFormatter.parseResolved0 (DateTimeFormatter.java:2108)
| at DateTimeFormatter.parse (DateTimeFormatter.java:2010)
| at LocalDateTime.parse (LocalDateTime.java:494)
| at (#1:1)

jshell>