[java] Support 'date-time-local' format

[Allsimon]

See https://spec.openapis.org/registry/format/date-time-local.html

fixes #13889

@cachescrubber (2022/02) @welshm (2022/02) @MelleD (2022/02) @atextor (2022/02) @manedev79 (2022/02) @javisst (2022/02) @borsch (2022/02) @banlevente (2022/02) @Zomzog (2022/09) @martin-mfg (2023/08)

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---

Summary by cubic

Add support for the OpenAPI date-time-local format in the Java/Spring generator. Maps to LocalDateTime (java.time.LocalDateTime) and parses defaults when the java8 date library is used; fixes #13889.

• New Features
  • Map date-time-local → LocalDateTime in AbstractJavaCodegen; always import java.time.LocalDateTime; add ModelUtils.isDateTimeLocalSchema.
  • Parse date-time-local defaults via LocalDateTime.parse(...) when using java8 (including nested object properties). Add unit tests (Java + Spring) and regenerate samples (Pet.adoptionDate with default).

^{Written for commit 1674477. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 3 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java">

<violation number="1" location="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java:2661">
P2: New format handling uses mismatched keys (`date-time-local` vs `local-date`), so the added `date-time-local` property post-processing branch will not execute.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[wing328]

https://github.com/OpenAPITools/openapi-generator/actions/runs/23816722621/job/69487441944?pr=23395

please update the samples to fix this

[cubic-dev-ai]

1 issue found across 7 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java">

<violation number="1" location="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java:1417">
P2: `date-time-local` default generation is incorrectly limited to `dateLibrary=java8`, so `java8-localdatetime` silently loses declared defaults.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}

[Chrimle]

LGTM