Spring Boot and Docker

Docker allows you to package an application with its dependencies, into a light weight, portable container that can run on almost any environment.  You can think of a Docker container as a run time, a mini virtual machine that encapsulates your application and its dependencies.
In order to run a container you need a Docker image. An image is like a template that defines everything that will exist within the container. You can almost think of an container as a run time instance of the image it was created from. In this post we'll define and build 3 slightly different Docker images that run a simple Java app.

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