The first blog I would recommend to continue learning about Docker will be Arun Gupta's blog, available at http://blog.arungupta.me. Arun, who first started blogging about Docker in July 2014, is the VP of developer advocacy at Couchbase, a Java champion, a JUG leader, and a Docker captain. He writes about many things on his blog; you can filter the content to only related to Docker using the #docker tag, using the link: http://blog.arungupta.me/tag/docker/.
You will find a lot of useful stuff here, related to Java development and Docker. He also authored a great Docker tutorial, available on GitHub: https://github.com/arun-gupta/docker-tutorial.
Next comes the official Docker blog, available at https://blog.docker.com. You will not ...