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Comment by ploxiln | Hacker News Reader

I'm all for replacing java bloat with a little bit of go, but it seems like the cause of the bloat becoming a real problem was hopping on the docker bandwagon, for a collection of services that always run together in an appliance and really benefited from being hosted in a shared JVM?

Isn't the JVM + servlet container thing supposed to be able to isolate the different services? They get their own bunch of threads, and their faults probably shouldn't crash other servlets?

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You should read Sun's J2EE specs. There is little semantic distinction between a stateless session bean and a container hosted micro-service. The specs were never fully grasped (imo) by the Java community and those who got it (per gossip I heard) -- appserver vendors e.g. IBM, JBoss, etc. -- effectively crippled the spec by resisting the completion of the APIs that would commoditize their containers.

Sun was really ahead of the game in various fronts.

So true. I had to read the entirety of the JSP spec (and a few others) when I was an intern to help the company do some static analysis things. I also read a good chunk of Tomcat. Sun had this grand vision of App servers which you could just push code to and it would run completely isolated. The app servers where supposed to be spec compliant meaning your app could run on any implementation. But, and this is what bit the company I was working for, all of the implementations add lots of non-standard bits and broke standard bits. This meant that if you had written your app to go on WebSphere there was essentially no way it was going to run on TomCat without modification.

If Sun had more tightly controlled the marketplace for these things I think the whole ecosystem would have been more robust.

Most of our problems are self-inflicted.

Traditionally you'd deploy a bunch of apps to one container (Tomcat, or whatever) and they'd all share the same JVM. I'm not sure if jars are shared in this way or not. I think OSGI was supposed to allow deploy apps to reuse the same jars and resources but I don't know how commonly that is deployed.

Now it is more common to run Tomcat or Jetty embedded for your app so that they are isolated.

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