WebSocket Server

// Create a Server with a ServerConnector listening on port 8080.
Server server = new Server(8080);

// Create a ContextHandler with the given context path.
ContextHandler contextHandler = new ContextHandler("/ctx");
server.setHandler(contextHandler);

// Create a WebSocketUpgradeHandler that implicitly creates a ServerWebSocketContainer.
WebSocketUpgradeHandler webSocketHandler = WebSocketUpgradeHandler.from(server, contextHandler, container ->
{
    // Configure the ServerWebSocketContainer.
    container.setMaxTextMessageSize(128 * 1024);

    // Map a request URI to a WebSocket endpoint, for example using a regexp.
    container.addMapping("regex|/ws/v\\d+/echo", (rq, rs, cb) -> new EchoEndPoint());

    // Advanced registration of a WebSocket endpoint.
    container.addMapping("/ws/adv", (rq, rs, cb) ->
    {
        List<String> subProtocols = rq.getSubProtocols();
        if (subProtocols.contains("my-ws-protocol"))
            return new MyJettyWebSocketEndPoint();
        return null;
    });
});
contextHandler.setHandler(webSocketHandler);

// Starting the Server will start the ContextHandler and the WebSocketUpgradeHandler,
// which would run the configuration of the ServerWebSocketContainer.
server.start();

// Create a Server with a ServerConnector listening on port 8080.
Server server = new Server(8080);

// Create a ContextHandler with the given context path.
ContextHandler contextHandler = new ContextHandler("/ctx");
server.setHandler(contextHandler);

// Create a ServerWebSocketContainer, which is also stored as an attribute in the context.
ServerWebSocketContainer container = ServerWebSocketContainer.ensure(server, contextHandler);

// You can use WebSocketUpgradeHandler if you want, but it is not necessary.
// You can ignore the line below, it is shown only for reference.
WebSocketUpgradeHandler webSocketHandler = new WebSocketUpgradeHandler(container);

// You can directly use ServerWebSocketContainer from any Handler.
contextHandler.setHandler(new Handler.Abstract()
{
    @Override
    public boolean handle(Request request, Response response, Callback callback)
    {
        // Retrieve the ServerWebSocketContainer.
        ServerWebSocketContainer container = ServerWebSocketContainer.get(request.getContext());

        // Verify special conditions for which a request should be upgraded to WebSocket.
        String pathInContext = Request.getPathInContext(request);
        if (pathInContext.startsWith("/ws/echo") && request.getHeaders().contains("X-WS", "true"))
        {
            try
            {
                // This is a WebSocket upgrade request, perform a direct upgrade.
                boolean upgraded = container.upgrade((rq, rs, cb) -> new EchoEndPoint(), request, response, callback);
                if (upgraded)
                    return true;
                // This was supposed to be a WebSocket upgrade request, but something went wrong.
                Response.writeError(request, response, callback, HttpStatus.UPGRADE_REQUIRED_426);
                return true;
            }
            catch (Exception x)
            {
                Response.writeError(request, response, callback, HttpStatus.UPGRADE_REQUIRED_426, "failed to upgrade", x);
                return true;
            }
        }
        else
        {
            // Handle a normal HTTP request.
            response.setStatus(HttpStatus.OK_200);
            callback.succeeded();
            return true;
        }
    }
});

// Starting the Server will start the ContextHandler.
server.start();

Server server = new Server(8080);

ContextHandler contextHandler = new ContextHandler("/ctx");
server.setHandler(contextHandler);

// Create a WebSocketUpgradeHandler.
WebSocketUpgradeHandler webSocketHandler = WebSocketUpgradeHandler.from(server, contextHandler, container ->
{
    container.addMapping("/ws/chat/{room}", (upgradeRequest, upgradeResponse, callback) ->
    {
        // Retrieve the URI template.
        UriTemplatePathSpec pathSpec = (UriTemplatePathSpec)upgradeRequest.getAttribute(PathSpec.class.getName());

        // Match the URI template.
        String pathInContext = Request.getPathInContext(upgradeRequest);
        Map<String, String> params = pathSpec.getPathParams(pathInContext);
        String room = params.get("room");

        // Create the new WebSocket endpoint with the URI template information.
        return new MyWebSocketRoomEndPoint(room);
    });
});
contextHandler.setHandler(webSocketHandler);