:package: feat(Java): Update Java version to 11

[regazzoj]

• Use of HttpClient from Java instead of Apache

• [x] Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• [x] Ensure that the pull request title represents the desired changelog entry
• [x] Please describe what you did
• [x] Link to relevant issues in GitHub or Jira
• [ ] Link to relevant pull requests, esp. upstream and downstream changes
• [ ] Ensure you have provided tests - that demonstrates feature works or fixes the issue

Resolves #31

[regazzoj]

@lucaspanjer @cris @cowboyd @vbehar Hello, I am sorry to bother you but I did some changes in Jenkinsfile to use an newer JDK than 8. But it doesn't take effect because I don't have write access. Can you help me ?

[regazzoj]

@chiragnaik Let me know if you think some changes could be made.

[gpflaum]

The build is failing with this error: [2023-03-29T08:44:18.252Z] Caused by: java.lang.UnsupportedClassVersionError: org/jenkinsci/maven/plugins/hpi/ValidateMojo has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0

Build log shows it is building with Java 8: [2023-03-29T08:43:48.131Z] Java version: 1.8.0_362, vendor: Temurin, runtime: C:\tools\jdk-8\jre

This blog says that error will happen if Jenkinsfile isn't updated to remove Java 8 configurations. You've done that, and I don't know what else needs to change.

[regazzoj]

The build is failing with this error: [2023-03-29T08:44:18.252Z] Caused by: java.lang.UnsupportedClassVersionError: org/jenkinsci/maven/plugins/hpi/ValidateMojo has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0

Build log shows it is building with Java 8: [2023-03-29T08:43:48.131Z] Java version: 1.8.0_362, vendor: Temurin, runtime: C:\tools\jdk-8\jre

This blog says that error will happen if Jenkinsfile isn't updated to remove Java 8 configurations. You've done that, and I don't know what else needs to change.

I know, and it is because I don't have right access on this repo'.

In your link, there is a section talking about this problem =>

Note that changes to a plugin’s Jenkinsfile require write access to take effect in pull request builds. If you submit a pull request to a repository to which you do not have write access, any Jenkinsfile changes will be ignored with this message:
Jenkinsfile has been modified in an untrusted revision

Pending JENKINS-46795, the pull request will need to be refiled by someone with write access to ensure the Jenkinsfile changes take effect.

[Ryudo302]

The build is failing with this error: [2023-03-29T08:44:18.252Z] Caused by: java.lang.UnsupportedClassVersionError: org/jenkinsci/maven/plugins/hpi/ValidateMojo has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0 Build log shows it is building with Java 8: [2023-03-29T08:43:48.131Z] Java version: 1.8.0_362, vendor: Temurin, runtime: C:\tools\jdk-8\jre This blog says that error will happen if Jenkinsfile isn't updated to remove Java 8 configurations. You've done that, and I don't know what else needs to change.

I know, and it is because I don't have right access on this repo'.

In your link, there is a section talking about this problem =>

Note that changes to a plugin’s Jenkinsfile require write access to take effect in pull request builds. If you submit a pull request to a repository to which you do not have write access, any Jenkinsfile changes will be ignored with this message:
Jenkinsfile has been modified in an untrusted revision

Pending JENKINS-46795, the pull request will need to be refiled by someone with write access to ensure the Jenkinsfile changes take effect.

@regazzoj, I tried to fix the problem with another commit in the Jenkinsfile, but apparently it had no effect. Should I close this PR and open another from your fork?

[regazzoj]

The build is failing with this error: [2023-03-29T08:44:18.252Z] Caused by: java.lang.UnsupportedClassVersionError: org/jenkinsci/maven/plugins/hpi/ValidateMojo has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0 Build log shows it is building with Java 8: [2023-03-29T08:43:48.131Z] Java version: 1.8.0_362, vendor: Temurin, runtime: C:\tools\jdk-8\jre This blog says that error will happen if Jenkinsfile isn't updated to remove Java 8 configurations. You've done that, and I don't know what else needs to change.

I know, and it is because I don't have right access on this repo'. In your link, there is a section talking about this problem =>

Note that changes to a plugin’s Jenkinsfile require write access to take effect in pull request builds. If you submit a pull request to a repository to which you do not have write access, any Jenkinsfile changes will be ignored with this message:
Jenkinsfile has been modified in an untrusted revision

Pending JENKINS-46795, the pull request will need to be refiled by someone with write access to ensure the Jenkinsfile changes take effect.

@regazzoj, I tried to fix the problem with another commit in the Jenkinsfile, but apparently it had no effect. Should I close this PR and open another from your fork?

@Ryudo302 I don't know... It might be a good try to give ! Thanks !

[Ryudo302]

@regazzoj @gpflaum I think that I finally solved the problem :) I had to change the Jenkinsfile myself at a new branch created from master (called _masterjdk11). Then, I merged @regazzoj's branch into that branch. Finally, I merged the _masterjdk11 into master.