code: public Buffer getBroadcastQueue(String sessionId) {
  
          CmsSessionInfo sessionInfo = getSessionInfo(getSessionUUID(sessionId));
          if (sessionInfo == null) {
              // return empty message buffer if the session is gone or not available
              return BufferUtils.synchronizedBuffer(new CircularFifoBuffer(CmsSessionInfo.QUEUE_SIZE));
          }
          return sessionInfo.getBroadcastQueue();
      }
docs: Returns the broadcast queue for the given OpenCms session id.<p>
  
  @param sessionId the OpenCms session id to get the broadcast queue for
  
  @return the broadcast queue for the given OpenCms session id