A Start to Finish Guide to Docker with Java

https://stackify.com/guide-docker-java/

Docker for Java developers

https://github.com/arun-gupta/docker-for-java

Running your first container

```shell script

start docker daemon

$ sudo dockerd

$ docker login

run container interactively (downloads it from registry if not present)

$ docker container run -it jboss/wildfly

run container in background

$ docker container run -d jboss/wildfly

list active containers

$ docker container ls

list all containers

$ docker container ls -a

stop container by id or name

$ docker container stop

run container setting a name

$ docker container run –name wildfly -d jboss/wildfly

removes a container even if running

$ docker container rm -f wildfly

starts container and executes a single command instead of wildfly server.

$ docker container run –name wildfly -it jboss/wildfly bash

now we are inside the container.

[jboss@d20566e5550b ~]$ pwd /opt/jboss

exit and finish container.

[jboss@d20566e5550b ~]$ exit $

## Ports

```shell script
# -P runs the container and redirects traffic to a random port
$ docker container run --name wildfly -P -d jboss/wildfly

# see the port
$ docker container ls

ONTAINER ID        IMAGE               COMMAND                  CREATED              STATUS              PORTS                     NAMES
9adb133f5324        jboss/wildfly       "/opt/jboss/wildfly/…"   About a minute ago   Up About a minute   0.0.0.0:32769->8080/tcp   wildfly

# see wildfly container logs
$ docker container logs wildfly

Open in web browser: http://localhost:32769/

```shell script

-p 8080:8080 we specify the redirection ports

$ docker container run –name wildfly -p 8080:8080 -d jboss/wildfly

Open in web browser: http://localhost:32769/

## Volume Mapping 

Mapping/mounting a local directory into a container.

```shell script
# remove the existent wildfly container.

# volume mapping with -v option
$ docker container run -d --name web -p 8080:8080 -v `pwd`/webapp.war:/opt/jboss/wildfly/standalone/deployments/webapp.war jboss/wildfly

Now the webapp is running in the container: http://localhost:8080/webapp/resources/persons

Create your first Docker Image (Dockerfile)

Create an empty directory, then create a Dockerfile.

```shell script $ vim Dockerfile

```dockerfile
FROM ubuntu
 
CMD echo "Hello world!"

```shell script $ docker image –help

build the image, tag helloworld, . this context

$ docker image build -t helloworld .

history

$ docker history helloworld

run helloworld container

$ docker container run helloworld

If the directory ins't empty, then its contents will be sent to the container. 

## Create your first Java Docker Image (Dockerfile)

Explore DockerHub: https://hub.docker.com/_/openjdk

In a new directory, then create a Dockerfile:

```dockerfile
FROM openjdk
CMD java -version

Then build (setting a tag name) and run the image:

```shell script $ docker image build -t hellojava .

$ docker image ls

$ docker container run hellojava penjdk version “13.0.1” 2019-10-15 OpenJDK Runtime Environment (build 13.0.1+9) OpenJDK 64-Bit Server VM (build 13.0.1+9, mixed mode, sharing)

Using alpine image which is smaller:

```dockerfile
FROM openjdk:jdk-alpine
CMD java -version

```shell script $ docker image build -t hello-jdk-alpine .