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by native_samples 1737 days ago
Hmm, fat jars still work OK in latest Javas. What is the issue is with Jakarta multi-release JARs? A MR JAR is just a regular JAR with files in different directories. They should fat-jar together OK.

There's certainly no requirement to start using Docker images!
2 comments
mumblemumble 1737 days ago
The problem I've run into with mrjars is that they tend to break libraries that do a bunch of classpath scanning. Mrjars add some stuff to the classpath that the older tools didn't understand and would choke on.

It's one of those things I would personally argue is a naughty hack that should be avoided if at all possible, but it's also something that's historically been ubiquitous within the Java ecosystem. It's frequently how convention-over-configuration dependency injection (as found in Spring Boot or Jersey) tends to be done, for example.

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pabl0rg 1737 days ago
Specifically, I was unable to find the gradle shadow/maven shade rules needed to use the jdk9+ version of the multi-release dependency "com.sun.xml.ws:jaxws-rt:2.3.5".

The reply I got on Stackoverflow from the person I think is the maintainer is "don't use fat jars", which is probably the correct solution, although most people use fat jars.

Lately, I've been reading that layered docker images should be a faster way to build and deploy java apps that have many tens of MB of dependencies that never change. It only works if you don't use fat jars.

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