Installing Java 17 instead of Java 8

[AlbertoPimpo]

Since Java 8 is no more compatible with Jenkins since version 2.361.1 (see jenkins docs), so there is no more reason to install it in the image.

Instead, since the same version (see jenkins docs), Jenkins supports Java 17, so it makes sense to install it in the image so that early adopters can already try it.

[openshift-ci[bot]]

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[openshift-ci[bot]]

Hi @AlbertoPimpo. Thanks for your PR.

I'm waiting for a openshift member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[coreydaley]

We can add Java 17 probably, but we can not remove Java 8 yet. There are some users which may still use Java 8 in their jobs so we want it to continue to be available.

[AlbertoPimpo]

We can add Java 17 probably, but we can not remove Java 8 yet. There are some users which may still use Java 8 in their jobs so we want it to continue to be available.

I'm not sure how many people are going to use it. Consider that by default the execution of jobs in the built-in node is de facto disabled (configured with 0 executors) and in general is discouraged (see jenkins docs).

[coreydaley]

I believe that in our images that is not disabled by default yet.

[AlbertoPimpo]

I believe that in our images that is not disabled by default yet.

You're actually right. I checked and the built-in node is not disabled by default, it is used if it is the only node that you have.

So, the only case in which you could benefit having Java 8 is the case in which you don't have any external node or k8s integration and you need to run a specific job that can only run on Java 8. Given that, I think it is safe to drop it. If you don't think so I will put it back in the PR.

[openshift-bot]

Issues go stale after 90d of inactivity.

Mark the issue as fresh by commenting /remove-lifecycle stale. Stale issues rot after an additional 30d of inactivity and eventually close. Exclude this issue from closing by commenting /lifecycle frozen.

If this issue is safe to close now please do so with /close.

/lifecycle stale

[coreydaley]

/close

[openshift-ci[bot]]

@coreydaley: Closed this PR.

In response to [this](https://github.com/openshift/jenkins/pull/1708#issuecomment-1911310646): >/close Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes/test-infra](https://github.com/kubernetes/test-infra/issues/new?title=Prow%20issue:) repository.