[java] Support 'time-local' format

[Allsimon]

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

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---

Summary by cubic

Adds support for the OpenAPI time-local format in Java generators. Models now use java.time.LocalTime with correct default handling when using the java8 date library.

• New Features
  • Map time-local to LocalTime and add the import when using the java8 date library.
  • Generate defaults with LocalTime.parse(...); keep string defaults for non-java8.
  • Add ModelUtils.isTimeLocalSchema and handle nested property defaults.
  • Update Spring tests and petstore samples (new feedingTime property).

^{Written for commit 97fe053. Summary will update on new commits.}

[cubic-dev-ai]

3 issues 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="samples/openapi3/client/petstore/spring-cloud-date-time/src/main/java/org/openapitools/model/Pet.java">

<violation number="1" location="samples/openapi3/client/petstore/spring-cloud-date-time/src/main/java/org/openapitools/model/Pet.java:44">
P2: New `LocalTime` model field is generated without Spring `@DateTimeFormat`, unlike other temporal fields, creating a Spring formatting/binding parity gap for `time-local`.</violation>
</file>

<file name="samples/client/petstore/spring-cloud-date-time/src/main/java/org/openapitools/model/Pet.java">

<violation number="1" location="samples/client/petstore/spring-cloud-date-time/src/main/java/org/openapitools/model/Pet.java:44">
P2: New `LocalTime` model field is missing `@DateTimeFormat(iso = DateTimeFormat.ISO.TIME)`, causing inconsistent and potentially non-ISO Spring binding versus other temporal fields.</violation>
</file>

<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: `time-local` defaults are skipped for `java8-localdatetime` because default generation checks `"java8".equals(getDateLibrary())` while type mapping uses `dateLibrary.startsWith("java8")`.</violation>
</file>

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

[cubic-dev-ai]

P2: New LocalTime model field is generated without Spring @DateTimeFormat, unlike other temporal fields, creating a Spring formatting/binding parity gap for time-local.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At samples/openapi3/client/petstore/spring-cloud-date-time/src/main/java/org/openapitools/model/Pet.java, line 44:

<comment>New `LocalTime` model field is generated without Spring `@DateTimeFormat`, unlike other temporal fields, creating a Spring formatting/binding parity gap for `time-local`.</comment>

<file context>
@@ -40,6 +41,8 @@ public class Pet {
   @DateTimeFormat(iso = DateTimeFormat.ISO.DATE)
   private LocalDate dateOfBirth = LocalDate.parse("2021-01-01");
 
+  private LocalTime feedingTime = LocalTime.parse("10:15:30");
+
   public Pet() {
</file context>

Suggested change

	private LocalTime feedingTime = LocalTime.parse("10:15:30");
	@DateTimeFormat(iso = DateTimeFormat.ISO.TIME)
	private LocalTime feedingTime = LocalTime.parse("10:15:30");

[Allsimon]

@DateTimeFormat is not needed since Spring Boot 3

Do I need to add it ? I'm not sure any Spring Boot 2 users will want to use a recent generator anyway... see #23269

[Allsimon]

I'm also open to create another PR that drop this annotation

[cubic-dev-ai]

P2: time-local defaults are skipped for java8-localdatetime because default generation checks "java8".equals(getDateLibrary()) while type mapping uses dateLibrary.startsWith("java8").

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java, line 1417:

<comment>`time-local` defaults are skipped for `java8-localdatetime` because default generation checks `"java8".equals(getDateLibrary())` while type mapping uses `dateLibrary.startsWith("java8")`.</comment>

<file context>
@@ -1411,6 +1412,13 @@ public String toDefaultValue(CodegenProperty cp, Schema schema) {
             return null;
+        } else if (ModelUtils.isTimeLocalSchema(schema)) {
+            if (schema.getDefault() != null) {
+                if ("java8".equals(getDateLibrary())) {
+                    return String.format(Locale.ROOT, "LocalTime.parse(\"%s\")", schema.getDefault());
+                }
</file context>