/** Websocketを開く. */
  private void openWebsocket() {
    boolean isSSL = isSSL();
    String host = getHost();
    int port = getPort();

    String sessionKey = getClientId();
    if (sessionKey == null) {
      Toast.makeText(DConnectActivity.this, "Client is not created.", Toast.LENGTH_LONG).show();
      return;
    }
    boolean result =
        HttpEventManager.INSTANCE.connect(
            host,
            port,
            isSSL,
            sessionKey,
            new CloseHandler() {
              @Override
              public void onClosed() {
                runOnUiThread(
                    new Runnable() {
                      @Override
                      public void run() {
                        Toast.makeText(DConnectActivity.this, "Websocket Close.", Toast.LENGTH_LONG)
                            .show();
                      }
                    });
              }
            });
    if (result) {
      Toast.makeText(DConnectActivity.this, "Websocket open.", Toast.LENGTH_LONG).show();
    } else {
      Toast.makeText(DConnectActivity.this, "Failed to open websocket.", Toast.LENGTH_LONG).show();
    }
  }
  @Override
  protected void onCreate(final Bundle savedInstanceState) {
    if (BuildConfig.DEBUG) {
      AndroidHandler handler = new AndroidHandler("deviceconnect.uiapp");
      handler.setFormatter(new SimpleFormatter());
      handler.setLevel(Level.ALL);
      mLogger.addHandler(handler);
      mLogger.setLevel(Level.ALL);
    } else {
      mLogger.setLevel(Level.OFF);
    }

    mLogger.entering(getClass().getName(), "onCreate", savedInstanceState);
    super.onCreate(savedInstanceState);

    mDConnectClient = new HttpDConnectClient();
    HttpEventManager.INSTANCE.setOrigin(getPackageName());

    (new ServiceDiscoveryTask()).execute();

    mLogger.exiting(getClass().getName(), "onCreate");
  }