Enterprise Java development in Emacs running in a Docker container

This container is powered by the following open source software products:

• Emacs 26
• Eclipse Oxygen with OpenJDK 8
• eclim -- eclim brings Eclipse functionality to the Vim editor

phusion/baseimage is used as the base image.

$ docker build -t emacs-eclim .

After building, you can just pull the image and run it.

$ docker run -it --name=emacs-eclim \
             -p 8080:8080 \
             emacs-eclim:latest \
             /sbin/my_init -- su - docker

This will start xvfb service in order to create a fake display for Eclipse, and then drop you in a shell with docker user.

Inside the container, start Eclipse via eclimd.

$ DISPLAY=:1 ./eclipse/eclimd

You should wait for the following message before connecting from Vim.

INFO  [org.eclim.eclipse.EclimDaemon] Eclim Server Started on: 127.0.0.1:9091

Alternatively, you can start eclimd with background option.

$ DISPLAY=:1 ./eclipse/eclimd -b

$ emacs

TODO - add first eclim step

Since this is a Docker environment, you will lose all changes in your container when you kill it (unless you do docker commit).

You can use Docker volumes with bind mount to map the host directories/files to the container.

For example,

$ docker run -it --name=emacs-eclim \
             -v /path/to/myproject:/home/docker/workspace/myproject \
             vim-eclim:latest \
             /sbin/my_init -- su - docker

Then change the owner of the project folder and files in the container

$ sudo chown -R docker:docker ~/workspace/myproject

My Java projects are mirrored in remote git repositories via ssh access and some of them uses Maven or Ivy. So I usually start the container with something like the following:

$ docker run -it --name=vim-eclim \
             -v /path/to/myproject:/home/docker/workspace/myproject \
             -v /path/to/ssh:/home/docker/.ssh \
             -v /path/to/gitconfig:/home/docker/.gitconfig \
             -v /path/to/m2:/home/docker/.m2 \
             -v /path/to/ivy2:/home/docker/.ivy2 \
             vim-eclim:latest \
             /sbin/my_init -- su - docker

For further details about Docker volumes, see the Docker Cheat-Sheet

This Docker images was inspired by the following project:

• https://github.com/snowch/docker-vim-eclim