This image contains a default configuration of Java OpenJDK 7 JRE based on jakubzapletal/ubuntu:14.04.
This image is published under Jakub Zapletal's repository on the Docker Hub and all you need as a prerequisite is having Docker installed on your machine.
The Dockerfile and supporting configuration files are available in the Github repository. This comes specially handy if you want to change any configuration or simply if you want to know how the image was built.