OpenJDK

Creating and deploying a Java 8 runtime container image

By Syed M Shaaf February 26, 2019February 25, 2019

A Java runtime environment should be able to run compiled source code, whereas a development kit, for example, OpenJDK, would include all the libraries/binaries to compile and run the source code. Essentially the latter is a superset of the runtime environment. More details on OpenJDK support and lifecycle can be found here.

Red Hat ships and supports container images with OpenJDK for both Java 8 and 11. More details are here. If you are using Red Hat Middleware, the s2i images shipped are also useful to deploy, for example, on Red Hat Openshift Container Platform.

Note that Red Hat only provides OpenJDK-based Java 8 and 11 images. With that said, there will certainly be situations where developers would like to create their own Java runtime images. For example, there could be reasons such as minimizing storage to run a runtime image. On the other hand, a lot of manual work around libraries such as Jolokio or Hawkular and even security parameters would need to be set up as well. If you’d prefer not to get into those details, I would recommend using the container images for OpenJDK shipped by Red Hat.

In this article we will:

• Build an image with Docker as well as Buildah.
• We will run that image with Docker as well as Podman on localhost.
• We will push our image to Quay.
• Finally, we will run our app by importing a stream into OpenShift.

This article was written for both OpenShift 3.11 and 4.0 beta. Let’s jump right into it.