/**
   * Creates a <tt>MediaFormat</tt> for the specified <tt>encoding</tt>, <tt>clockRate</tt>,
   * <tt>channels</tt> and set of format parameters. If <tt>encoding</tt> is known to this
   * <tt>MediaFormatFactory</tt>, returns a <tt>MediaFormat</tt> which is either an
   * <tt>AudioMediaFormat</tt> or a <tt>VideoMediaFormat</tt> instance. Otherwise, returns
   * <tt>null</tt>.
   *
   * @param encoding the well-known encoding (name) to create a <tt>MediaFormat</tt> for
   * @param clockRate the clock rate in Hz to create a <tt>MediaFormat</tt> for
   * @param frameRate the frame rate in number of frames per second to create a <tt>MediaFormat</tt>
   *     for
   * @param channels the number of available channels (1 for mono, 2 for stereo) if it makes sense
   *     for the <tt>MediaFormat</tt> with the specified <tt>encoding</tt>; otherwise, ignored
   * @param formatParams any codec specific parameters which have been received via SIP/SDP or
   *     XMPP/Jingle
   * @param advancedParams any parameters which have been received via SIP/SDP or XMPP/Jingle
   * @return a <tt>MediaFormat</tt> with the specified <tt>encoding</tt>, <tt>clockRate</tt>,
   *     <tt>channels</tt> and set of format parameters which is either an <tt>AudioMediaFormat</tt>
   *     or a <tt>VideoMediaFormat</tt> instance if <tt>encoding</tt> is known to this
   *     <tt>MediaFormatFactory</tt>; otherwise, <tt>null</tt>
   * @see MediaFormatFactory#createMediaFormat(String, double, int, float, Map, Map)
   */
  public MediaFormat createMediaFormat(
      String encoding,
      double clockRate,
      int channels,
      float frameRate,
      Map<String, String> formatParams,
      Map<String, String> advancedParams) {
    MediaFormat mediaFormat = createMediaFormat(encoding, clockRate, channels, formatParams);

    if (mediaFormat == null) return null;

    /*
     * MediaFormatImpl is immutable so if the caller wants to change the
     * format parameters and/or the advanced attributes, we'll have to
     * create a new MediaFormatImpl.
     */
    Map<String, String> formatParameters = null;
    Map<String, String> advancedParameters = null;

    if ((formatParams != null) && !formatParams.isEmpty()) formatParameters = formatParams;
    if ((advancedParams != null) && !advancedParams.isEmpty()) advancedParameters = advancedParams;

    if ((formatParameters != null) || (advancedParameters != null)) {
      switch (mediaFormat.getMediaType()) {
        case AUDIO:
          mediaFormat =
              new AudioMediaFormatImpl(
                  ((AudioMediaFormatImpl) mediaFormat).getFormat(),
                  formatParameters,
                  advancedParameters);
          break;
        case VIDEO:
          VideoMediaFormatImpl videoMediaFormatImpl = (VideoMediaFormatImpl) mediaFormat;

          /*
           * If the format of VideoMediaFormatImpl is
           * a ParameterizedVideoFormat, it's possible for the format
           * parameters of that ParameterizedVideoFormat and of the new
           * VideoMediaFormatImpl (to be created) to be out of sync. While
           * it's not technically perfect, it should be practically safe
           * for the format parameters which distinguish VideoFormats with
           * the same encoding and clock rate because mediaFormat has
           * already been created in sync with formatParams (with respect
           * to the format parameters which distinguish VideoFormats with
           * the same encoding and clock rate).
           */
          mediaFormat =
              new VideoMediaFormatImpl(
                  videoMediaFormatImpl.getFormat(),
                  videoMediaFormatImpl.getClockRate(),
                  frameRate,
                  formatParameters,
                  advancedParameters);
          break;
        default:
          mediaFormat = null;
      }
    }
    return mediaFormat;
  }
  private void maybeDoShutdown() {
    if (shutdownInProgress && conferences.isEmpty()) {
      logger.info("Focus is shutting down NOW");

      ShutdownService shutdownService =
          ServiceUtils.getService(FocusBundleActivator.bundleContext, ShutdownService.class);

      shutdownService.beginShutdown();
    }
  }