the decline of Java application servers when using docker containers — fabric8 io — Medium

the docker way to work with Java Application Servers is to make an immutable image for the application server and the deployment units you wish to run in production.

To upgrade the Java code of a service, rather than dropping a WAR in the webapps/deploy folder or calling a REST/JMX API in the application server or whatever, you just make a new image with the new deployment unit inside and run it.

Increasingly the Java Application Server doesn’t need to worry about deploying and undeploying new code at runtime; it doesn’t need to watch a deploy folder for changes or listen on a REST/JMX API for requests to change its deployment; it just starts up the code in its image on startup.

So the very idea of a Java Application Server (a dynamic JVM which you deploy and undeploy code to) is very much in the decline in a docker world.

the decline of Java application servers when using docker containers — fabric8 io — Medium