Building RESTful Web Services with Java EE 8

ConnectionCallback

The second type of callback that is optionally supported is ConnectionCallback. Here, you can specify a custom implementation. Currently, the only method you need to implement is the onDisconnect method, which is passed the actual AsyncResponse. This method is called if the client is connected prematurely. According to JSR 339, the support for ConnectionCallback is optional:

    static class LoggingConnectionCallback implements       ConnectionCallback {        @Override        public void onDisconnect(AsyncResponse disconnected) {            LOGGER.log(Level.INFO, "Client disconnected on {0}.",               disconnected);        }