无法在Heroku Node.js服务器上连接websocket java客户端

Question

我试图通过Jetty websockets将我的Java客户端连接到Heroku上的Node.js服务器，但是没有连接。 @OnWebSocketConnect方法不会执行。

    WebSocketClient client = new WebSocketClient();
    SimpleEchoSocket socket = new SimpleEchoSocket();

    try {
        client.start();
        URI echoUri = new URI(destUri);
        ClientUpgradeRequest request = new ClientUpgradeRequest();
        client.connect(socket, echoUri, request);
        socket.awaitClose(50, TimeUnit.SECONDS);
    } catch (Throwable t) {
        t.printStackTrace();
    } finally {
        try {
            client.stop();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }