Book Image

Docker and Kubernetes for Java Developers

By : Jarosław Krochmalski
Book Image

Docker and Kubernetes for Java Developers

By: Jarosław Krochmalski

Overview of this book

Imagine creating and testing Java EE applications on Apache Tomcat Server or Wildfly Application server in minutes along with deploying and managing Java applications swiftly. Sounds too good to be true? But you have a reason to cheer as such scenarios are only possible by leveraging Docker and Kubernetes. This book will start by introducing Docker and delve deep into its networking and persistent storage concepts. You will then proceed to learn how to refactor monolith application into separate services by building an application and then packaging it into Docker containers. Next, you will create an image containing Java Enterprise Application and later run it using Docker. Moving on, the book will focus on Kubernetes and its features and you will learn to deploy a Java application to Kubernetes using Maven and monitor a Java application in production. By the end of the book, you will get hands-on with some more advanced topics to further extend your knowledge about Docker and Kubernetes.
Table of Contents (12 chapters)
11
More Resources

Dockerfile instructions

We will begin with the instruction that every Dockerfile must have at the top, the FROM instruction.

FROM

This is the first instruction in the Dockerfile. It sets the base image for every subsequent instruction coming next in the file. The syntax for the FROM instruction is straightforward. It's just:

FROM <image>, or FROM <image>:<tag>, or FROM <image>@<digest>

The FROM instruction takes a tag or digest as a parameter. If you decide to skip them, Docker will assume you want to build your image from the latest tag. Be aware that latest will not always be the latest version of the image you want to build upon. The latest tag is kind of a special one. Also, it may not...