Java Actor Projects

Quasar

6 4,547 0.0 Java

Fibers, Channels and Actors for the JVM (by puniverse)

Project mention: Java 21 makes me like Java again | news.ycombinator.com | 2023-09-16

Java 21 doesn't retrofit green threads though. Quasar [0] is a library that implemented fibers for Java and the main developer pron has joined the OpenJDK development team. All that was necessary for first party support is to make the JDK libraries yield when blocking.
Adopting async isn't impossible at all, there is very little demand for it.
[0] https://docs.paralleluniverse.co/quasar/

blockbuster

1 159 7.5 Java

The Machinima Studio mod (by mchorse)
WorkOS

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NOTE: The open source projects on this list are ordered by number of github stars. The number of mentions indicates repo mentiontions in the last 12 Months or since we started tracking (Dec 2020).