code: public void forceDisconnect(String sessionId, String connectionId) throws OpenTokException , InvalidArgumentException, RequestException {
          if (sessionId == null || sessionId.isEmpty() || connectionId == null || connectionId.isEmpty()) {
              throw new InvalidArgumentException("Session or Connection string null or empty");
          }
          try {
              this.client.forceDisconnect(sessionId, connectionId);
  
          } catch (Exception e)
          {
              throw e;
          }
      }
docs: Disconnect a client from an OpenTok session
  <p>
  Use this API to forcibly terminate a connection of a session.
  
  @param sessionId The session ID of the connection
  @param  connectionId The connection ID to disconnect