Friday, October 23, 2015

Re: What is j2cl?

On Saturday, October 24, 2015 at 12:14:17 AM UTC+2, Marko wrote:
I see the term "j2cl" comming up in several threads connected with GWT 3.0. What does it mean?

I speculate that this is a "Java-to-Closure-Library" transpiler, which would be GREAT, because you wouldn't depend on JRE emulation library anymore and GWT 3.0 would be safe from "Oracle copyright lawsuit nonsense". Additionally you could integrate JavaScript Closure Library code with Java code transpiled to Closure Library and it would use the exactly same class library... I guess also that Google would profit from such a transpiler in Google Inbox and other similar projects...

I hope I am not speculating too much into the Google's trade secrets and that this post will not be deleted because of this... :-)

You're almost right (Googlers will correct me if I'm wrong).

j2cl stands for Java-to-CLosure. It's not much about the Closure Library but rather the Closure Compiler. It's a transpiler from Java to Closure-annotated ES6 (there are a couple videos about this from the GWT Meetup earlier this year: ), type annotations will help the Closure Compiler prune unused code to further optimize the produced JS.

But it won't free us from the JRE emulation library.

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