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Comment by js4all | Hacker News Reader

So its basically a reinvention of the servlet container model. Shield equals tomcat or one of the other servlet container apps. Caplets equal war file packaged applications. Have I missed something?

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Capsule does not resemble servlet containers and WAR files at all. You can think of Capsule as a fat jar that always works and contains a startup script (which is declarative and placed in the JAR's manifest). It is a packaging solution. It isn't a deployment format (like a WAR), but a JAR that can configure the JVM that runs it.

And while the word "container" is used here, we mean a different kind of containers -- those that give you virtualization and app isolation at the OS level[1]. So there is no container -- like a sevlet container -- that hosts multiple applications, and no specific programming model.

[1]: https://en.wikipedia.org/wiki/Operating-system-level_virtual...

An, that's interesting. So can it be used to overcome the memory leak problems of traditional servlet containers, because every app is a system process whose memory is released by the OS and not by the container.

Well, it's completely orthogonal, really. Capsule makes it very easy to package and deploy single-app servlet containers (like, say, Jetty), but if you wanted to you could also package JBoss as a single capsule JAR. If it can run on the JVM -- it can be packaged with Capsule (and if not, let us know and we'll fix it!)

Thanks for the explanation. I will definitely try Capsule.

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