[JAVA-SPRING] - 22859 - spring http interface library should support 'useBeanValidation'

[Picazsoo]

Spring declares that Http Interface annotations can also be used server-side for controller instantiation: https://docs.spring.io/spring-framework/reference/integration/rest-clients.html#rest-http-service-client

On the server side, an @controller class can implement the same interface to handle requests with @HttpExchange controller methods. In such case it makes sense to allow the bean validation option and thus annotate both the model and the api methods with jakarta.validation annotations.

I also added unit tests

closes #22859

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---

Summary by cubic

Adds Bean Validation support to the spring-http-interface library (reactive and non‑reactive) and fixes Jackson polymorphic typing with discriminator mappings while avoiding NPEs in nullable containers. Also corrects an invalid regex in the test fixture so generated @Pattern uses "[a-zA-Z]". Validation is opt‑in (useBeanValidation/performBeanValidation default false); when enabled we emit jakarta.validation, @Validated, and add spring-boot-starter-validation. Fixes #22859.

• New Features

  • Honor useBeanValidation/performBeanValidation only when provided; add spring-boot-starter-validation when either is true; add reactive and non‑reactive bean‑validation samples and include them in the JDK 17 workflow with tests.
  • For Kotlin spring-declarative-http-interface, add spring-boot-starter-validation when useBeanValidation is true and add a new server sample to the Kotlin JDK 17 workflow.

• Refactors

  • Stop emitting redundant @Valid on container fields in POJOs; update samples.
  • Propagate discriminator mapping keys as x-discriminator-value and emit @JsonTypeName to ensure correct Jackson polymorphic typing.

^{Written for commit 889b377. Summary will update on new commits. Review in cubic}

[cubic-dev-ai]

5 issues found across 217 files

Note: This PR contains a large number of files. cubic only reviews up to 75 files per PR, so some files may not have been reviewed.

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/resources/JavaSpring/libraries/spring-http-interface/pom-sb4.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/pom-sb4.mustache:101">
P2: `spring-boot-starter-validation` is only added for `useBeanValidation`, but `performBeanValidation` can be enabled independently for spring-http-interface. When `performBeanValidation=true` and `useBeanValidation=false`, generated code can require Bean Validation at runtime without pulling the validation implementation, leading to missing validator beans.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/NullableMapPropertyDto.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/NullableMapPropertyDto.java:43">
P1: `putLanguageValuesItem` dereferences a null map when `languageValues` is explicitly set to null via `JsonNullable.of(null)`.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/api/FakeApi.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/api/FakeApi.java:219">
P2: @Pattern uses Java regex syntax; `/[a-z]/i` is treated literally (slashes and `i` included), so case-insensitive matching won’t work and normal alphabetic input will fail validation.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/PetDto.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/PetDto.java:41">
P3: @Valid is applied to both the field and getter for tags, which causes cascaded validation to run twice per Bean Validation spec and can produce duplicate violations/overhead. Use a single access strategy (field or property) for @Valid.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/CatDto.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/CatDto.java:36">
P2: `CatDto` is missing explicit `@JsonTypeName("Cat")`, risking discriminator `className` mismatch under Jackson `Id.NAME`.</violation>
</file>

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

[cubic-dev-ai]

4 issues found across 645 files

Note: This PR contains a large number of files. cubic only reviews up to 75 files per PR, so some files may not have been reviewed.

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/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/FormatTestDto.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/FormatTestDto.java:205">
P1: Bean Validation regex is emitted in JavaScript `/.../i` form instead of Java regex/flags, causing incorrect `@Pattern` validation behavior.</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/ContainerDefaultValueDto.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/ContainerDefaultValueDto.java:35">
P2: Required properties are pre-initialized to non-null values, so `@NotNull` cannot catch missing JSON fields and required-field validation can be bypassed.</violation>

<violation number="2" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/ContainerDefaultValueDto.java:52">
P2: `add...Item` methods can throw `NullPointerException` when the field is `JsonNullable.of(null)` (present but null).</violation>
</file>

<file name="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/NullableMapPropertyDto.java">

<violation number="1" location="samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/NullableMapPropertyDto.java:42">
P2: `putLanguageValuesItem` can throw `NullPointerException` when `languageValues` is `JsonNullable.of(null)` (present wrapper with null value).</violation>
</file>

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

[cubic-dev-ai]

P2: Required properties are pre-initialized to non-null values, so @NotNull cannot catch missing JSON fields and required-field validation can be bypassed.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At samples/client/petstore/spring-http-interface-bean-validation/src/main/java/org/openapitools/model/ContainerDefaultValueDto.java, line 35:

<comment>Required properties are pre-initialized to non-null values, so `@NotNull` cannot catch missing JSON fields and required-field validation can be bypassed.</comment>

<file context>
@@ -0,0 +1,204 @@
+
+  private JsonNullable<List<String>> nullableRequiredArray = JsonNullable.<List<String>>undefined();
+
+  private List<String> requiredArray = new ArrayList<>();
+
+  private JsonNullable<List<String>> nullableArrayWithDefault = JsonNullable.<List<String>>undefined();
</file context>

[cubic-dev-ai]

No issues found across 676 files

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Re-trigger cubic}