Chapter 1. Red Hat build of OpenJDK applications in containers
Red Hat build of OpenJDK images have default startup scripts that automatically detect application JAR
files and launch Java. The script’s behavior can be customized using environment variables. For more information, see /help.md
in the container.
The Java applications in the /deployments
directory of the OpenJDK image are run when the image loads.
Containers that contain Red Hat build of OpenJDK applications are not automatically updated with security updates. Ensure that you update these images at least once every three months.
Application JAR
files can be fat JARs or thin JARs.
- Fat JARs contain all of the application’s dependencies.
Thin JARs reference other JARs that contain some, or all, of the application’s dependencies.
Thin JARs are only supported if:
- They have a flat classpath.
-
All dependencies are JARs that are in the
/deployments
directory.