webSocket.send("...World!");
    webSocket.send(ByteString.decodeHex("deadbeef"));
    webSocket.close(1000, "Goodbye, World!");
  }

  @Override public void onMessage(WebSocket webSocket, String text) {
    System.out.println("MESSAGE: " + text);
  }

  @Override public void onMessage(WebSocket webSocket, ByteString bytes) {
    System.out.println("MESSAGE: " + bytes.hex());
  }