[JAVA][BUG] Do not use valueOf for numeric types for generating inner enums Current Master

[timon-sbr]

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Technical Comittee

@bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @martin-mfg (2023/08)

Description

The template file src/main/resources/Java/modelInnerEnum.mustache was using the valueOf() method to create instances for enum fields. This does not work for every Object, because valueOf() is not implemented in every possible Object. BigDecimal for example does not provide the valueOf(BigDecimal) method. This behaviour results in invalid code through generation.
To fix this, I decided to only use the valueOf method, for non numeric types. It seems the decision to use the valueOf method was, to fix a bug for Boolean values (see: PR-19815 ). So this fix should be non breaking.

This PR closes #20188

[timon-sbr]

Hi @martin-mfg I've created a new PR based on the current Master. Could you please check if I've cherry picked your changes correctly? Thank you :-)

[jorgerod]

Hi @timon-sbr @martin-mfg

This PR is great but I have seen that despite the changes added in the PR, there are still compilation errors in some case related to Object.valueOf which is wrong

For example:

• Case 1:

   components:
     schemas:
       MyDto:
         description: test
         type: object
         properties:
           OrderStatus:
             $ref: './destinationUrl.yml'

  destinationUrl.yml:

   title: "The Destination URL Object"
   type: object
   description: Destination URL.
   properties:
     taskType:
       enum:
           - PENDING
           - PROCESSING
     owner:
       type: string

  Generated code:

   public class DestinationUrlDTO implements Serializable {
     private static final long serialVersionUID = 1L;
   
     /**
      * Gets or Sets taskType
      */
     public enum TaskTypeEnum {
       PENDING(Object.valueOf("PENDING")),
       
       PROCESSING(Object.valueOf("PROCESSING"));

• Case 2:

    components:
      schemas:
        MyDto:
          description: test
          type: object
          properties:
   		    OrderStatus:
   		      type: string
   		      description: Order status
   		      additionalProperties: false
   		      enum:
   		        - PENDING
   		        - PROCESSING

  Generated code:

   public class MyDtoDTO implements Serializable {
     private static final long serialVersionUID = 1L;
   
     /**
      * Order status
      */
     public enum OrderStatusEnum {
       PENDING(Object.valueOf("PENDING")),
       
       PROCESSING(Object.valueOf("PROCESSING"));

This problem can be solved by adding this check (isFreeFormObject) to what you have added in your PR:

    {{{name}}}({{^isUri}}{{^isNumeric}}{{^isFreeFormObject}}{{dataType}}.valueOf({{/isFreeFormObject}}{{/isNumeric}}{{/isUri}}{{{value}}}{{^isUri}}{{^isNumeric}}{{^isFreeFormObject}}){{/isFreeFormObject}}{{/isNumeric}}{{/isUri}}){{^-last}},

@timon-sbr @martin-mfg @wing328 What do you think?

[martin-mfg]

Hi @jorgerod, thanks for the suggestion! Could either you (in a new PR) or @timon-sbr (in the current PR) please make the suggested changes, apply it to all relevant *.mustache files, and merge the latest master? Thanks!

[jorgerod]

Hi @jorgerod, thanks for the suggestion! Could either you (in a new PR) or @timon-sbr (in the current PR) please make the suggested changes, apply it to all relevant *.mustache files, and merge the latest master? Thanks!

@timon-sbr Do you want to make them yourself?

[timon-sbr]

Hi @jorgerod, thanks for the suggestion! Could either you (in a new PR) or @timon-sbr (in the current PR) please make the suggested changes, apply it to all relevant *.mustache files, and merge the latest master? Thanks!

@timon-sbr Do you want to make them yourself?

Hi @jorgerod sorry for the late reply. I will integrate the suggested changes in this pr and regenerate the samples.

[timon-sbr]

Hi @martin-mfg and @jorgerod
I've integrated the suggested changes in all relevant template files and added a String type enum to petstore API for testing. Could you please review the changes?

[martin-mfg]

Why is isFreeFormObject not used here, like in the other changed files?
Same question applies to modules/openapi-generator/src/main/resources/java-helidon/server/libraries/mp/enumClass.mustache and modules/openapi-generator/src/main/resources/java-helidon/client/libraries/mp/enumClass.mustache.

And the same also applies to using isUri.

[timon-sbr]

Hi @martin-mfg thx for the review. I've fixed the missing parts.

[martin-mfg]

Object.valueOf doesn't exist. There are several other occurrences in other files as well. Please fix.

[timon-sbr]

After regenerating the samples the problem is solved.

[wing328]

please review the CI failures when you've time, e.g. https://github.com/OpenAPITools/openapi-generator/actions/runs/15417950869/job/43385774859?pr=21055

[schophil]

Hi I recently had the same issue and I found this PR that should solve it.
But is anyone still looking at this PR?