Websockets

Undertow provides support for Websockets out of the box. Undertow core provides a XNIO based API, which uses the Xnio Channel interface to provide access to the web socket at a low level.

Most users will want a higher level interface than this, and to that end Undertow also provides a JSR-356 implementation. This implementation is part of a separate jar, to use it you must make sure that you have the undertow-servlet and undertow-websocket-jsr artifacts on your class path. Servlet support is required because the JSR-356 API is based on the Servlet API.

For maven users the following snippet should be added to your pom.xml:

<dependency>
  <groupId>io.undertow</groupId>
  <artifactId>undertow-servlet</artifactId>
  <version>${version.io.undertow}</version>
</dependency>

<dependency>
  <groupId>io.undertow</groupId>
  <artifactId>undertow-websockets-jsr</artifactId>
  <version>${version.io.undertow}</version>
</dependency>