We Keep Coding

how to call java from ubuntu inside the docker

I was trying to extract dump.jar file then convert to csv file using this java command in ubuntu-docker (Linux platform) the code has no syntax error but there is no java, so it cannot process. How shall I call java from ubuntu inside the docker?
install Java but there is not enough space
ANY IDEA please?

trying
connect container with user root
docker exec -it -u root container_name /bin/bash
install java 11 or other version
apt-get install openjdk-11-jdk
java --version
now you can use java in docker container

The most correct way to run MyBatis migration from a Docker container

I'm trying to figure out how and when to run the mybatis schema migrations from a Docker container deployed inside a Docker Swarm. I mean: I need the most correct way to do that.
At the moment We build a Docker container from a Dockerfile
FROM ubuntu:18.04
RUN apt-get update && apt-get install -y \
openjdk-11-jre \
openjdk-11-jdk \
maven
ARG JAR_FILE=target/*.jar
COPY ${JAR_FILE} app.jar
COPY start.sh start.sh
RUN chmod +x start.sh
ENTRYPOINT ["/bin/sh","start.sh"]
then the start.sh script contains
mvn resources:resources migration:up -Dmigration.path="target/classes/migrations" -Dmigration.env=development -Papply_migrations
java -jar /app.jar
But in this way we have to build an image from Ubuntu, install Maven and lunch the migrations with the environment "hardcoded" into the start.sh file, so We need different files from different envs.
What do you think is the most correct method to run these scheme migrations during the build/deployment process?
Thanks in advance.
EDIT:
I've found useful the solution to use the mybatis migration docker image found on DockerHub and posted by #h3adache but still to have an Issue trying to execute it on a DockerSwarm: the issue is related to the volume mounted between the host folder with mybatis migrations files and the container folder "/migration"
-v $PWD:/migration
My docker-compose.yml is
mybatis-migration:
image: mybatis/migrations
volumes:
- ./mybatis-migrations:/migration
command:
- up
It works fine locally against a dockerized MySQL but fails during the deploy with a GitLab pipeline.
The ./mybatis-migrations folder is, obviously, on my localhost when I checkout the code and It is in the build path of the GitLab repository when the GitLab runner builds everything but is not on the DockerSwarm host so it's unable to find that directory.
This is the error message:
invalid mount config for type "bind": bind source path does not exist
How can I fix this?

Let's look to the problem with maven first. I understand that you (quite rightfully) don't want to install maven (and probably JDK).
There are two ways to achieve what you need.
Runtime Schema Upgrade
You can run migration right from your application when it starts. It may be run from the main method or from the custom javax.servlet.ServletContextListener if you deploy a web application.
Here's how it may look like:
new UpOperation().operate(
new DataSourceConnectionProvider(dataSource),
new JavaMigrationLoader("mycompany.migration.script"), null, null);
Check the documentation with details how to configure this.
This would require to only include mybatis migration to the dependencies of your project (which you might already have).
Using mybatis migrations library directly
The other way is to run mybaits migration directly that is without maven. This can be done by installing the library inside docker as described in the documentation. Note that you only need the libraryr itself and JRE, so no JDK and maven is required.
Then you can run migration using migrate script that is part of the distribution archive.
Environment
In order to fix this you can pass that as a parameter to the docker container that runs start.sh. One option is to use environment variable via --env option for docker service create or docker run. The variable passed this way can be accessed as a regular environment variable in linux in your start.sh.

I suggest you follow the guide I posted on medium which uses the official Mybatis Migrations docker hub image
It gives you an 'out of the box' docker experience and allows you to target different environments (as mentioned in my post).
tl;dr
Use https://hub.docker.com/r/mybatis/migrations for your base image.
This gives you migration commands out of the box
Instead of using the .gitlab-ci.yml from the post, you can add the action (eg. migrate up) as your docker image entrypoint or command.
You can control env or directly affect parameters used by using docker --env
eg.
docker run \
--rm \
--env "MIGRATIONS_URL=jdbc:mysql://$(hostname):3306/mb_migration" \
-v $PWD:/migration \
-it mybatis/migrations status

How can i access through ssh spring shell cli

I am trying to implement a simple cli application ( executable jar file running in linux docker image) using spring-shell library. After i started the Docker image with "docker run -it -p 8080:8080 springshelldemo" command my spring-shell app starts and the cli is available in cmd. How can i access this spring-shell cli from a second cmd using docker exec command (or some other better way) ?
I need this in order to make my app available to more than 1 users at the same time.

I found the answer to this problem. There is this great library on top of spring shell https://github.com/fonimus/ that gives you ssh functionality and with proper docker run file command you can access the spring shell through ssh with all features present.

why doesn't jenkins start my java program?

This is extremely annoying but I have a script launch.sh like:
#!/bin/bash -x
java -jar foo.jar &
If I run it by hand, my java program starts up. However in Jenkins I configured that just does execute shell: $HUDSON_HOME/launch.sh >& out
I see from out file that it looks like it started java, but when I do a ps I don't see it there. How do I configure jenkins appropriately?

https://wiki.jenkins-ci.org/display/JENKINS/ProcessTreeKiller
add
export BUILD_ID=dontKillMe
to shell script

How to run a Docker image from a Java program?

That's what I would do in the command line:
$ docker run -i imagename mycommand
Should I just use Runtime.getRuntime().exe()? Should I use one of the available Java APIs?
From what I've seen, the APIs would help me to pull and push images, but all I want is to run a particular command on a particular public image, and I don't seem to find an easy way to do that with the APIs.
I'm attaching the actual command I'd be executing, just in case:
$ docker run --rm -p 8080:8080 -i owasp/zap2docker-stable zap.sh -daemon -port 8080

You should think to use java api to manage docker images/container.
You can start with any of them
Java docker-java https://github.com/docker-java/docker-java Active
Java docker-client https://github.com/spotify/docker-client Active
Refer:
Docker Remote API client libraries