[BUG][Java][okhttp] POST request with an empty body results in a NullPointerException

[pg-fine]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

Sending a POST request with an empty body results in a NullPointerException.
This issue exists since version 5.3.1.

Unexpected exception thrown: java.lang.NullPointerException: Parameter specified as non-null is null: method okhttp3.MediaType$Companion.parse, parameter $this$toMediaTypeOrNull
org.opentest4j.AssertionFailedError: Unexpected exception thrown: java.lang.NullPointerException: Parameter specified as non-null is null: method okhttp3.MediaType$Companion.parse, parameter $this$toMediaTypeOrNull

openapi-generator version

OpenAPI 5.4.0 and OpenAPI 5.3.1

OpenAPI declaration file content or url

see https://github.com/pg-fine/openapi-post-empty-body-bug

Generation Details

see https://github.com/pg-fine/openapi-post-empty-body-bug

Steps to reproduce

see https://github.com/pg-fine/openapi-post-empty-body-bug

Related issues/PRs

4ecceb1

"* remove default content-type in java okhttp client" is the reason for this bug

Suggest a fix

add a default content-type or allow empty request bodies with empty content-types.

[wing328]

add a default content-type or allow empty request bodies with empty content-types.

I prefer the latter. May I know if you can help contribute a fix for it?

[pg-fine]

I prefer the latter. May I know if you can help contribute a fix for it?

I also prefer the latter. My first suggestion would only be a quick fix and not solve the problem per se.
Unfortunately, I have no idea how to fix this correctly since I have no overview of all implications a change would bring.

[QuyetVV2]

Hi there, did the problem resolved ?

[codemolition22]

Hello, is there already a new status regarding this issue?

[fileme]

This issue is resolved in 6.2.0.
pg-fine/openapi-post-empty-body-bug#1

[pg-fine]

Thanks for your help @fileme !