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Is there a way to create docker image containing docker and java

I want to create a Docker image with Java and Docker installed on it. The idea is that the eventual docker container should be able to create Docker images. My Java application executes commands like docker build -t my-image ..
That is why I need Docker installed in my Docker container

In the past I solved the same issue writing the following Dockerfile:
FROM maven:3.6.3-jdk-8
USER root
# Install docker CLI for docker images generation inside the container itself
RUN apt update -y
RUN apt install -y curl
RUN curl https://get.docker.com/builds/Linux/x86_64/docker-latest.tgz | tar xvz -C /tmp/ && mv /tmp/docker/docker /usr/bin/docker
# Customize here your container with your instructions...
Of course, you can change the FROM image as per you needs.

How do we mount a file as file instead of directory inside docke container?

I want to execute a file in new docker container lets say i want to execute Hello.java which prints Hello World. I want to execute this file inside new docker container.
docker run -it -v /Hello.class:/Hello.class alpine:latest ls -l
I would fire above command using Runtime class of java.
It shows that Hello.class is a directory.
I want it as a file so that i can execute it inside new docker container.
How to do this??

Hello I would suggest to make a small dockerfile for simplicity.
Step1: Create Dockerfile:
FROM openjdk:7
COPY . .
WORKDIR /usr/src/app
RUN javac HelloClass.java
CMD ["java", "HelloClass"]
Step 2: Building the Docker Container
After you have created both the JavaMain Class and the Dockerfile, you can now use the Docker build command to build your Docker Image.
docker build -t hello-demo .
Step 3: Running the Docker Container
Now, you can use the Docker run command to run your Docker Container.
docker run -it hello-demo

how to access mysql docker container in spring boot docker container

i have 2 docker file
1. mysql-dockerfile
FROM mysql:5.5
EXPOSE 3306
ENV MYSQL_ROOT_PASSWORD root
ENV MYSQL_DATABASE ToDoList
command used to build dockerfiles are as below
sudo docker build -t mysql-img -f mysql-dockerfile .
sudo docker run -d --name mysqlcontainer -p 3030:3306 mysql-img
2. java-dockerfile
FROM openjdk:8-jre-alpine
EXPOSE 9090
WORKDIR /usr/src
COPY target/*.war todoApp.war
CMD ["java","-jar","todoApp.war"]
command used to build dockerfiles are as below
sudo docker build -t java-img -f java-dockerfile .
docker run --name javacontainer -d -p 4040:9090 java-img
spring boot application consist jdbc url as follow
spring.datasource.url=jdbc:mysql://localhost:3030/ToDoList
i am not able to start project because spring boot application in docker is not able to connect mysql db which is in another container.
one solution i found is to bring two docker container in one docker network or link docker container.
can anyone please suggest good solution, modified docker run command and modified jdbc url.

Put them into one network and use container names as hostnames:
docker network create foo
docker run --network=foo --name mysqlcontainer -d mysql-img
docker run --network=foo --name javacontainer -d java-img
Dont expose ports - they are exposed automatically between containers inside network.
To connect inside, use mysqlcontainer:3306 and javacontainer:9090.
To connect from host, you will need port exposing.

Building a docker image from dockerfile, can't get java to run correctly, but can run java from image as command line parameters in docker run command

I am new to docker and dockerfile files, having just started trying to write them. I have built a simple java console application and can successfully build a docker image from a dockerfile, but if I include
CMD ["java","-jar","app.jar"]
when I try to run the image I always get a bin/sh error, typically "java not found" or the like.
However, when I don't include the CMD line and just use this Dockerfile to build my image
FROM openjdk:8-jre-alpine
COPY app.jar /app.jar
and then run
docker run -it --rm my-container:tag
I can then run
java -jar app.jar
and the application runs as expected.
I can also run
docker run -it --rm my-container:tag java -jar app.jar
and the application runs as expected.
Every guide I read says I should be able to use CMD or ENTRYPOINT as written above, but nothing ever works.
What might I be missing in this simple example?
Thank you,
Trevor
EDIT: I am running docker version 18.06.1-ce-mac73 (26764) on MacOS Sierra. I am not positive that docker works this way, but I have two image versions in my public docker hub. The dockerfile for v1 is:
FROM openjdk:8-jre-alpine
COPY 454calendar.jar app.jar
The dockerfile for v2 is:
FROM openjdk:8-jre-alpine
ENV PROJECT_DIR=/app
WORKDIR $PROJECT_DIR
COPY 454calendar.jar $PROJECT_DIR
If I add
CMD [“java”,”-jar”,”454calendar.jar”]
to the v2 dockerfile and rebuild, I get this error with the docker run command.
/bin/sh: [“java”,”-jar”,”454calendar.jar”]: not found
Without the CMD line, I can run container and it starts right into the /app working directory where I can run the java command and execute the program.
The two versions of the container in my public docker repository do not have the CMD line in their respective dockerfiles.

The solution was maddeningly simple. Thanks to #Rakesh, I checked the configuration for TextEdit on MacOS and saw that Smart Quotes was turned on. Once I turned off that option and retyped the double quotes, then rebuilt and ran the docker container, the application started up just as expected.

I don't see any problem with your approach. I was able to make a HelloWorld application to run with the below Dockerfile.
FROM openjdk:8-jre-alpine
RUN mkdir /app
RUN cd /app
COPY HelloWorld.jar /app/HelloWorld.jar
WORKDIR /app
CMD ["java","-jar", "HelloWorld.jar"]
I'm on the following docker version
docker -v
Docker version 18.06.1-ce, build e68fc7a
docker-compose -v
docker-compose version 1.22.0, build f46880f

How make a dspace docker work space?

I have a little experience with docker-compose and Laravel, this set goes fine, but how could I make the same with dspace?
I would like to have work directory in my host, not all into container.
I have tried dspace-docker that is in dockerhub, is this one: https://github.com/4Science/dspace-docker, but I had troubles wit him.
Thank you!

The following Docker images can be used to run DSpace locally. There is not yet a published Docker Compose file.
- https://hub.docker.com/r/dspace/dspace-tomcat/
- https://hub.docker.com/r/dspace/dspace-postgres-pgcrypto/
The following page describes how to utilize these images on either Windows or MacOS: https://github.com/DSpace-Labs/DSpace-Docker-Images/blob/master/tutorial.md
Here are the key steps.
Clone DSpace
Configure a local.cfg file that assumes DSpace will run in a container. [dspace-install] will be within the container.
Run the DSpace maven build on your workstation
Run the DSpace ant update in a container to install the code at [dspace-install]
The MacOS setup is described here. See the link above for Windows.
docker network create dspacenet
docker volume create pgdataD6
docker run -it -d --network dspacenet -p 5432:5432 --name dspacedb -v pgdataD6:/pgdata -e PGDATA=/pgdata dspace/dspace-postgres-pgcrypto
docker run -it --rm --network dspacenet -v "$(pwd)"/dspace/target/dspace-installer:/installer -v dspaceD6:/dspace -w /installer dspace/dspace-tomcat ant update clean_backups
docker run -it --network dspacenet -v dspaceD6:/dspace -p 8080:8080 --name dspacetomcat -e DSPACE_INSTALL=/dspace dspace/dspace-tomcat