[JAVA][FEIGN] Removing hardcoded HTTP Client which is causing performance issues

[sushma3690]

Fixing performance issues due to Hardcoded HTTP client

1. Breaking change was introduced here. (Somehow, the PR got merged despite a review comment suggested to revert the same in 2023 for a different reason)
2. This is causing performance issues as new tcp connection is created for each new request which is caught in performance tests.
3. Lot of TCP connections are created which in turn results in exceeded CPU utilisation and eventually timeout errors as all the resources are exhausted. For example, below image shows the number of TCP connections opened by my application which is using feign client to be 64. For 64 requests, it should have been able to reuse the 1 connection with connection pooling instead of creating 64 connections.

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[wing328]

@sushma3690 thanks for the PR 🙏

Somehow, the PR got merged despite a review comment suggested to revert the same

Can you please share the URL to the comment? I reviewed the PR again but couldn't find it.

[sushma3690]

1. here

@wing328 Here is the comment url.

[wing328]

thanks. i missed that

cc @hugo-ma-alves (author of the PR in question)

[sushma3690]

@wing328 I will generate the samples and update the PR

[wing328]

https://github.com/OpenAPITools/openapi-generator/actions/runs/14430406203/job/40464641609?pr=21085

please update the samples (step 3 in pr checklist) to fix the CI failure.

[sushma3690]

@wing328 I have updated the samples, Can you please do the needful to trigger the workflows. Thank you

[sushma3690]

++ Adding Java committee

@wing328 / @bbdouglas / @sreeshas / @jfiala / @lukoyanov / @cbornet / @jeff9finger / @karismann / @Zomzog / @lwlee2608 / @martin-mfg I have updated the samples, Can someone please do the needful to trigger the workflows.

Thank you

[wing328]

https://github.com/OpenAPITools/openapi-generator/actions/runs/14430865853/job/40702608092?pr=21085

let me know if you need help fixing it

[sushma3690]

https://github.com/OpenAPITools/openapi-generator/actions/runs/14430865853/job/40702608092?pr=21085

looking into it. will get back in few minutes

[sushma3690]

https://github.com/OpenAPITools/openapi-generator/actions/runs/14430865853/job/40702608092?pr=21085

looking into it. will get back in few minutes

1. added missing samples @wing328

2. all Tests passed on running ./mvnw test

[sushma3690]

@wing328 All checks passed, can you please approve the PR so that we can merge it. Thank you !

[wing328]

just merged it. thanks for the contribution

[lesteenman]

This has introduced a backwards incompatible change: #21187.

[wing328]

@lesteenman thanks for reporting the issue

@sushma3690 can you please review the issue when you've time?