WebSocket implements AutoCloseable { boolean isConnected() { return session != null && session.isOpen(); } WebSocket(
      String username,
      String password,
      URI uri,
      ObjectMapper mapper,
      TLSConfig.Factory tlsConfigFactory,
      long keepAliveSeconds,
      EventHandler eventHandler,
      ErrorHandler errorHandler,
      CloseHandler closeHandler); @Override void close();  }
@Test public void isConnected_sessionNull() throws Exception { assertThat(underTest.isConnected(), is(false)); }