[SPRING] Improve jSpecify Nullable for all args constructor, fluent setters and Builder and toIndentedString

[jpfinne]

when useJspecify=true:

• add @Nullable on fluent setters, all argument constructors and builder for non required attributes. Honor openApiNullable, useOptional and optionalAcceptNullable . fixes [BUG] [JAVA] [SPRING] Missing JSpecify @Nullable on fluent setter parameter for optional properties #23681 Supersedes [JAVA-SPRING] Fix missing nullable on all args constructor and fluent setters #24263
• fix [BUG][JAVA][Spring] with jspecify - non-required field with default should be annotated with @Nullable #24294 for Spring (default value handling)
• update lambda.jSpecifyNullable to generate @Nullable List<java.time.Instant> instead of List<java.time.@Nullable Instant)

For all spring options:

• fix [BUG][JAVA][SPRING] Nullaways warn with JSpecify #22598 (String toIndentedString(@Nullable Object o)

Add unit tests in SpringCodegenTest
Add 2 more spring samples

Example using useOptional=true and optionalAcceptNullable=true

public Foo color(@Nullable String color) {
    this.color = Optional.ofNullable(color);
    return this;
  }

useOptional=true and optionalAcceptNullable=false

public Foo color(String color) {
    this.color = Optional.of(color);
    return this;
  }

ps: this PR focuses on jspecify. There are still some missing @jakarta.annotation.Nullable when useJspecify=false.
It avoids regenerating too many samples. That is for another PR. There are comments in the mustache template like {{!backward compatibility}} to locate the code to fix.

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  Commit all changed files.
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Review welcome:
@cachescrubber (2022/02) @welshm (2022/02) @atextor (2022/02) @manedev79 (2022/02) @javisst (2022/02) @borsch (2022/02) @banlevente (2022/02) @Zomzog (2022/09) @martin-mfg (2023/08) @KannaKim (2026/07)

---

Summary by cubic

Improves JSpecify @Nullable in Spring generators: we annotate all-args constructors and builder/fluent setters, place @Nullable correctly on qualified types and generics, and honor openApiNullable, useOptional, and optionalAcceptNullable. Adds Spring Boot 4 configs/samples, maps OffsetDateTime to java.time.Instant, and updates samples with a color query param and related fields.

• New Features

  • All-args constructors and builder chain setters add @Nullable when useJspecify=true, honoring openApiNullable, useOptional, and optionalAcceptNullable; packages marked @NullMarked.
  • New Spring Boot 4 configs: spring-boot-4-jspecify-openapiNullable.yaml and spring-boot-4-jspecify-useOptional.yaml; OffsetDateTime -> java.time.Instant, BigDecimal -> java.math.BigDecimal.
  • API/models: add color query param (default red) and related fields; samples regenerated across clients/servers; CI/workflows include new sample dirs and fix naming to springboot-4-jspecify.

• Bug Fixes

  • Correct JSpecify placement before generics via getLastIndex, yielding java.time.@Nullable Instant and @Nullable List<java.time.Instant>.
  • Use nullableDatatypeWithEnum in Java/nullableArgumentWithEnum.mustache; builder setters use nullableArgument_builder.
  • Split nullableAnnotation.mustache into nullableAnnotation_jspecify.mustache and nullableAnnotation_default.mustache for correct rules and backward compatibility.
  • Mark toIndentedString(@Nullable Object o) across samples and add test assertions for optionalAcceptNullable=true/false.

^{Written for commit 3f3a174. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 131 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/client/petstore/java/native-jackson3-jspecify/src/main/java/org/openapitools/client/model/Foo.java">

<violation number="1" location="samples/client/petstore/java/native-jackson3-jspecify/src/main/java/org/openapitools/client/model/Foo.java:626">
P2: The new builder chain setters for the nullable properties are missing `@Nullable` on their parameter types, even though this package is `@NullMarked` and the corresponding fluent setters/getters/fields are correctly annotated `@Nullable`. Under JSpecify this makes the builder parameters non-null, so `toBuilder()` passing `getNullableDt()`, `getNullableBinary()`, `getNullableNumber()`, `getColor()`, etc. (all `@Nullable` return types) into those setters is a nullness mismatch, and it directly contradicts the PR's goal of adding `@Nullable` to builder chain setters. Consider emitting `@Nullable` (in the same qualified form used by the fluent setters) for the builder setters of nullable properties so the builder API stays consistent with the rest of the model.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[jpfinne]

Cubic warning about invalid java samples is not relevant. Java generators are not updated in this PR.
The issue already existed.

[MelleD]

Hey @jpfinne,

I didn't see that case in the PR, but Iam unsure :).

For Optionals. I also have some warnings with ofNullable

  public Dto description(String description) {
    this.description = Optional.ofNullable(description);
    return this;
  }

[jpfinne]

@MelleD
in the generated samples/openapi3/server/petstore/springboot-4-jspecify-useOptional/src/main/java/org/openapitools/model/Foo.java

public Foo color(@Nullable String color) {
    this.color = Optional.ofNullable(color);
    return this;
  }

Is it what you want?

[MelleD]

Is it what you want?

Yes nice :)

[SubhamAshok]

Built this branch and tested locally. Findings:

• jspecify + spring-cloud: fields, getters, toIndentedString all @nullable, imports correct
• full tree diff vs master, jspecify off + useOptional: identical
• full tree diff vs master, jspecify on: only change is fluent setters gaining @nullable, as intended
• defaulted non-required field: now @Nullable Boolean force = false with @nullable setter. Resolves #24294, tested that exact example
• typeMapping to java.time.Instant: java.time.@Nullable Instant and @Nullable List<java.time.Instant> both correct, getLastIndex works

Nit: pojo.mustache line 137 uses {{>nullableAnnotation}}, line 156 {{>nullableAnnotation_default}}. Same output, one style is easier to maintain.

Includes my #24567 fix, happy to close it when this merges.