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

[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 issue-2694445144

[wing328]

@timon-sbr thanks for the PR.

Can you please add a test case or 2 in modules/openapi-generator/src/test/resources/3_0/java/petstore-with-fake-endpoints-models-for-testing-okhttp-gson.yaml and then regenerate the samples?

[timon-sbr]

@wing328 thanks for the review. I've added some test data to modules/openapi-generator/src/test/resources/3_0/java/petstore-with-fake-endpoints-models-for-testing-okhttp-gson.yaml and regenerated the samples. Can you please check, if this is enough? I'm not sure, if I've also have to add java code to test the behaviour.