CODEWITHSUNDEEP
javadockerwildflycentos7
Araphel
Araphel

Reputation: 307

Find and change the value of JAVA_HOME in centos/wildfly docker image

I'm just starting out with docker, so this may be a conceptual mistake -

I downloaded the centos/wildfly image from Docker Hub and wanted to change the JDK version of this server.
However, I couldn't find the JAVA_HOME value anywhere in the wildfly config files, and there isn't any java folder in usr
For this setup and image, where is it pulling the JDK path from ? Is there a way to access it and hopefully change it ?

Upvotes: 1

Views: 1320

Answers (1)

Adiii
Adiii

Reputation: 59966

If look into the official repository of centos/wildly, you will find something like

RUN yum -y install tar java-1.7.0-openjdk-devel

wildfly/centos7/Dockerfile

So you do not need to modify the existing image, just build your own image be updating JDK version in Dockerfile, build it and run the container from your own image.

Create your own Dockerfile and run the below command that's it.

docker build --tag=centos/wildfly-admin-jdk-1.8 .

docker run -it -p 9990:9990 centos/wildfly-admin-jdk-1.8

So here is the Dockerfile with JDK-1.8.0

# Use latest Fedora image as the base
FROM centos:latest
MAINTAINER http://www.centos.org

LABEL Vendor="CentOS"
LABEL License=GPLv2
LABEL Version=8.2.0.Final


# Update base image
RUN yum -y update && yum clean all

# xmlstarlet is useful when modifying attributes/elements
# saxon can be used to execute configuration transformation using XSLT
# augeas is a great tool to edit any configuration files (XML too)
# bsdtar can be used to unpack zip files using pipes
RUN yum -y install tar java-1.8.0-openjdk-devel saxon \ 
augeas bsdtar shadow-utils && yum clean all

# Set the WILDFLY_VERSION env variable
ENV WILDFLY_VERSION 8.2.0.Final

# Create the wildfly user and group
RUN groupadd -r wildfly -g 433 && useradd -u 431 -r -g wildfly -d /opt/wildfly -s /sbin/nologin -c "WildFly user" wildfly

# Create directory to extract tar file to
RUN mkdir /opt/wildfly-$WILDFLY_VERSION

# Add the WildFly distribution to /opt, and make wildfly the owner of the extracted tar content
RUN cd /opt && curl http://download.jboss.org/wildfly/$WILDFLY_VERSION/wildfly-$WILDFLY_VERSION.tar.gz | tar zx && chown -R wildfly:wildfly /opt/wildfly-$WILDFLY_VERSION

# Make sure the distribution is available from a well-known place
RUN ln -s /opt/wildfly-$WILDFLY_VERSION /opt/wildfly && chown -R wildfly:wildfly /opt/wildfly

# Set the JBOSS_HOME env variable
ENV JBOSS_HOME /opt/wildfly

# Expose the ports we're interested in
EXPOSE 8080 9990

# Run everything below as the wildfly user
USER wildfly

# Set the default command to run on boot
# This will boot WildFly in the standalone mode and bind to all interface
CMD ["/opt/wildfly/bin/standalone.sh", "-c", "standalone-full.xml", "-b", "0.0.0.0", "-bmanagement", "0.0.0.0"]

Upvotes: 2

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