code: public String getBroadcastMessageString() {
  
          CmsSessionInfo sessionInfo = OpenCms.getSessionManager().getSessionInfo(getSession());
          if (sessionInfo == null) {
              return null;
          }
          String sessionId = sessionInfo.getSessionId().toString();
          Buffer messageQueue = OpenCms.getSessionManager().getBroadcastQueue(sessionId);
          if (!messageQueue.isEmpty()) {
              // create message String
              StringBuffer result = new StringBuffer(512);
              // the user has pending messages, display them all
              while (!messageQueue.isEmpty()) {
                  CmsBroadcast message = (CmsBroadcast)messageQueue.remove();
                  result.append('[');
                  result.append(getMessages().getDateTime(message.getSendTime()));
                  result.append("] ");
                  result.append(key(Messages.GUI_LABEL_BROADCASTMESSAGEFROM_0));
                  result.append(' ');
                  if (message.getUser() != null) {
                      result.append(message.getUser().getName());
                  } else {
                      // system message
                      result.append(key(Messages.GUI_LABEL_BROADCAST_FROM_SYSTEM_0));
                  }
                  result.append(":\n");
                  result.append(message.getMessage());
                  result.append("\n\n");
              }
              return result.toString();
          }
          // no message pending, return null
          return null;
      }
docs: Returns the message String for the broadcast message alert of the workplace.<p>
  
  Caution: returns the pure message String (not escaped) or null, if no message is pending.<p>
  
  @return the message String for the broadcast message alert of the workplace