#Lab Solution

The quickest way is to copy the job you already have:

• browse to http://localhost:8080/view/all/newJob
• set the job name to hello-world
• choose Pipeline as the type
• in the Copy from box at the bottom, enter manual-gate
• click OK

In the job config, scroll to Triggers and tick Poll SCM. That sets a schedule for checking the Git server for changes. Enter this in the Schedule box:

* * * * *

Five stars means every minute. Jenkins checks the repo, and if anything has changed since the last build it triggers a new one. Polling is wasteful compared to a webhook, but it works without the Git server needing to reach Jenkins — which is why it's still common.

Change the Script Path to labs/jenkins/hello-world/Jenkinsfile, then save and build. It fails.

Open the build and read the console output. The Test stage fails with:

Error: Could not find or load main class HelloWorkd

HelloWorkd. That's a typo — the class is HelloWorld.

Fix the java HelloWorkd line in labs/jenkins/hello-world/Jenkinsfile so it reads java HelloWorld. A corrected copy is in this Jenkinsfile if you want to compare.

Then commit and push:

git add labs/jenkins/hello-world/Jenkinsfile

git commit -m 'Fix class name typo'

git push gitea main

Back in Jenkins, wait up to a minute for the SCM poll to trigger the build (or click Build Now if you're impatient).

This time it passes. On the build page you'll see an Archived Artifacts section containing HelloWorld.class — that comes from the archiveArtifacts step in the post { success { ... } } block of the Jenkinsfile. Archiving is how you keep the output of a build after the workspace is cleaned up.

Back to the exercises.