WebSockets come with Java EE 7 and require no additional dependencies or libraries. Particularly in "microservices architectures" websockets are an interesting option for the implementation of WAR to WAR communication.
In this screencast I created two WARs from scratch and let them communicate via WebSockets:
Web Apps, SPA, PWA with vanilla Java Script (ES 6+), CSS 3 and WebStandards only. As simple as possible, but not simpler. See you at: (Progressive) Web apps, Single Page Apps and WebStandards airhacks workshops at MUC airport, Winter Edition
airhacks.fm the podcast:
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