Openshift provide a base Java s2i image where we can use as a base image to run our java applicaiton. But too bad, the default Java base image is still using java 8. On this example, im trying to do a simple deployment to Openshift but using Java 11 as its base image, instead of Java 8.

First we need to import a Java 11 s2i image from Red Hat Registry, it will become our base image to run our executable java app.

oc import-image my-project/openjdk-11-rhel7 --from=registry.redhat.io/openjdk/openjdk-11-rhel7 --confirm

Next is creating a very simple pipeline script to build, and deploy our app using Jenkins Pipeline.

node('maven') {
	stage('Clone') {
		sh "git config --global http.sslVerify false"
		sh "git clone https://github.com/edwin/hello-world.git"
	}
	stage('Build') {
		sh "mvn -v"
		sh "mvn clean package -f hello-world/pom.xml"
		
		def jarFile = sh(returnStdout: true, script: 'find hello-world/target -maxdepth 1 -regextype posix-extended -regex ".+\\.(jar|war)\$" | head -n 1').trim()
		sh "cp ${jarFile} app.jar"
	}
	stage('Deploy') {
		sh "oc new-build --name hello-world --binary -n my-project --image-stream=my-project/openjdk-11-rhel7  || true"
		sh "oc start-build hello-world --from-file=app.jar -n my-project --follow --wait"
		sh "oc new-app hello-world || true"
		sh "oc expose svc/hello-world || true"
	}
}