Add support for JSpecify annotations in SpringCodegen

[felldo]

• Introduced useJSpecify flag to enable the use of JSpecify's @Nullable annotations.
• Modified POJO templates to correctly place JSpecify annotations for TYPE_USE compatibility.
• Updated importMappings to handle hardcoded JSpecify annotations when enabled.
• Added a test case for verifying correct annotation placement and behavior (issue_23206.yaml and corresponding Java test).
• fixes [BUG] [JAVA] [SPRING] Impossible to use JSpecify with SchemaMappings #23206

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Summary by cubic

Adds an optional useJSpecify flag in SpringCodegen to generate JSpecify @Nullable as a TYPE_USE annotation in POJOs and include the org.jspecify:jspecify dependency when enabled. Fixes incorrect @Nullable placement and enables JSpecify-compatible builds (fixes #23206).

• New Features

  • useJSpecify: when true, maps Nullable to org.jspecify.annotations.Nullable (overrides any user importMapping).
  • Emits @Nullable on the type for fields, getters, and setters (e.g., a.b.c.@Nullable TypeName).
  • Simplifies pojo.mustache to insert type-use annotations via x-jspecify-annotated-type.
  • Conditionally adds org.jspecify:jspecify:1.0.0 to Spring pom.mustache templates (spring-boot, spring-cloud, spring-http-interface).
  • Adds tests for schema-mapped and imported types; updates docs for Spring and Java Camel generators.

• Migration

  • Off by default. Enable with --additional-properties useJSpecify=true.

^{Written for commit a48a5ae. Summary will update on new commits.}

@bbdouglas @sreeshas @jfiala @lukoyanov @cbornet @jeff9finger @karismann @Zomzog @lwlee2608 @martin-mfg

[cubic-dev-ai]

1 issue found across 6 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="docs/generators/spring.md">

<violation number="1" location="docs/generators/spring.md:105">
P2: `useJSpecify` is documented and generates JSpecify annotation usage, but Spring build templates do not appear to add the required `org.jspecify:jspecify` dependency, risking uncompilable generated projects.</violation>
</file>

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[cubic-dev-ai]

P2: useJSpecify is documented and generates JSpecify annotation usage, but Spring build templates do not appear to add the required org.jspecify:jspecify dependency, risking uncompilable generated projects.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At docs/generators/spring.md, line 105:

<comment>`useJSpecify` is documented and generates JSpecify annotation usage, but Spring build templates do not appear to add the required `org.jspecify:jspecify` dependency, risking uncompilable generated projects.</comment>

<file context>
@@ -102,6 +102,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |useEnumCaseInsensitive|Use `equalsIgnoreCase` when String for enum comparison| |false|
 |useFeignClientContextId|Whether to generate Feign client with contextId parameter.| |true|
 |useFeignClientUrl|Whether to generate Feign client with url parameter.| |true|
+|useJSpecify|Use JSpecify's @Nullable (org.jspecify.annotations.Nullable) instead of Spring's @Nullable. Overrides any user-supplied importMapping for 'Nullable'.| |false|
 |useJackson3|Set it in order to use jackson 3 dependencies (only allowed when `useSpringBoot4` is set and incompatible with `openApiNullable`).| |false|
 |useJakartaEe|whether to use Jakarta EE namespace instead of javax| |false|
</file context>

[Chrimle]

Agree that the generated pom.xml will need a jspecify dependency... unless it's a transitive dependency already? 🤔

[felldo]

Agree that the generated pom.xml will need a jspecify dependency... unless it's a transitive dependency already? 🤔

Spring Boot 4 should already include JSpecify because they just switched to it from their own Null annotations. But earlier versions shouldn't provide it. So I guess we still need to add it?

[Chrimle]

Hmm... there is a configOption useSpring4/useSpring3... perhaps wrap the dependency import based on that or something?

Edit:

openapi-generator/modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-boot/application.mustache

Lines 3 to 8 in 5a70edb

	{{#useSpringBoot4}}
	spring.jackson.datatype.datetime.WRITE_DATES_AS_TIMESTAMPS=false
	{{/useSpringBoot4}}
	{{^useSpringBoot4}}
	spring.jackson.serialization.WRITE_DATES_AS_TIMESTAMPS=false
	{{/useSpringBoot4}}

It's useSpringBoot4.

So these files:

• JavaSpring/libraries/spring-boot/pom.mustache
• JavaSpring/libraries/spring-boot/pom-sb3.mustache
• JavaSpring/libraries/spring-boot/pom-sb4.mustache
• JavaSpring/libraries/spring-cloud/pom.mustache
• JavaSpring/libraries/spring-cloud/pom-sb3.mustache
• JavaSpring/libraries/spring-cloud/pom-sb4.mustache
• JavaSpring/libraries/spring-http-interface/pom.mustache
• JavaSpring/libraries/spring-http-interface/pom-sb4.mustache

[Chrimle]

Beautiful ❤️