fix(java): default values from allOfs are not correctly definied

[marceljk]

Description

When the api spec contains a object, where a property has a default value and uses an allOf to a primitive type, like long or float, the generated code can not be compiled because L or f are missing at the end of the defaultValue.

Api spec example:

openapi: 3.0.0
info:
  version: 0.1.0
  title: ''
  description: ''
paths:
  /foo:
    get:
      responses:
        default:
          description: response
          content:
            application/json:
              schema:
                type: object
                properties:
                  long:
                    $ref: '#/components/schemas/AllOfRefToLong'
                  float:
                    $ref: '#/components/schemas/AllOfRefToFloat'
                  double:
                    $ref: '#/components/schemas/AllOfRefToDouble'
components:
  schemas:
    LongId:
      description: "Id as long"
      type: integer
      format: int64
    Weight:
      description: "Weight as float"
      format: float
      type: number
    Height:
      description: "Height as double"
      format: double
      type: number
    AllOfRefToLong:
      description: "Object with allOf ref to long"
      type: object
      properties:
        id:
          allOf:
            - $ref: '#/components/schemas/LongId'
          default: 10
    AllOfRefToFloat:
      description: "Object with allOf ref to float"
      type: object
      properties:
        weight:
          allOf:
            - $ref: '#/components/schemas/Weight'
          default: 7.89
    AllOfRefToDouble:
      description: "Object with allOf ref to double"
      type: object
      properties:
        height:
          allOf:
            - $ref: '#/components/schemas/Height'
          default: 32.1

Generate a java client:

# generate
java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate --generator-name java --input-spec allOf-defaultValue.yaml --output "allOf-defaultValue-fix"

# run the tests
cd allOf-defaultValue-fix
chmod +x gradlew
./gradlew test

Compile error output without the fix:

> Task :compileJava FAILED
warning: [options] source value 8 is obsolete and will be removed in a future release
warning: [options] target value 8 is obsolete and will be removed in a future release
warning: [options] To suppress warnings about obsolete options, use -Xlint:-options.
/Users/<user>/tmp/openapi-generator/allOf-defaultValue-fix/src/main/java/org/openapitools/client/model/AllOfRefToLong.java:58: error: incompatible types: int cannot be converted to Long
  private Long id = 10;
                    ^
/Users/<user>/tmp/openapi-generator/allOf-defaultValue-fix/src/main/java/org/openapitools/client/model/AllOfRefToFloat.java:58: error: incompatible types: double cannot be converted to Float
  private Float weight = 7.89;
                         ^
2 errors
3 warnings

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':compileJava'.
> Compilation failed; see the compiler error output for details.

* Try:
> Run with --info option to get more log output.
> Run with --scan to get full insights.

Deprecated Gradle features were used in this build, making it incompatible with Gradle 9.0.

You can use '--warning-mode all' to show the individual deprecation warnings and determine if they come from your own scripts or plugins.

For more on this, please refer to https://docs.gradle.org/8.7/userguide/command_line_interface.html#sec:command_line_warnings in the Gradle documentation.

BUILD FAILED in 697ms
1 actionable task: 1 executed

Implementation

• In order to fix this issue, some additional checks were added in the toDefaultValue() function, to check for allOf schemas, if they are a long, double or float and return the defaultValue correctly defined

---

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

[wing328]

thanks for the fix

looks good to me

let's give it a try