Docker File for building image

Image Builds
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Hello-

I want to build a docker image for spring boot with tomcat enabled and JRE 21. I would run it later in Azure DevOps pipeline Agent based on RHEL 8.

I am creating the docker file but confused with the base image. i have created this docker file. Can anyone verify if this docker file i am missing anything ?

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Use Red Hat Universal Base Image (UBI) 8 as the base image

FROM registry.access.redhat.com/ubi8/ubi

Set environment variables

ENV JAVA_HOME=/usr/lib/jvm/java-11-openjdk
ENV PATH=$PATH:$JAVA_HOME/bin

Install OpenJDK 11 (replace with JDK 21 if available)

RUN yum install -y java-11-openjdk-devel &&
yum clean all

Copy the Spring Boot application JAR file into the container

COPY target/your-application.jar /app/your-application.jar

Expose port 8080 for Tomcat

EXPOSE 8080

Command to run the Spring Boot application

CMD [“java”, “-jar”, “/app/your-application.jar”]

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if i have JDK 21 on my self hosted agent VM, do i need below in docker file

Install OpenJDK 11 (replace with JDK 21 if available)

RUN yum install -y java-11-openjdk-devel &&
yum clean all

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