code: private boolean isVisibleForSite(final HttpServletRequest request, final Page page) {
  
  		final Site site = page.getSite();
  		if (site == null) {
  
  			return true;
  		}
  
  		final String serverName = request.getServerName();
  		final int serverPort    = request.getServerPort();
  
  		if (StringUtils.isNotBlank(serverName) && !serverName.equals(site.getHostname())) {
  			return false;
  		}
  
  		final Integer sitePort = site.getPort();
  
  		if (sitePort != null && serverPort != sitePort) {
  			return false;
  		}
  
  		return true;
  
  	}
docs: Check if the given page is visible for the requested site defined by
  a hostname and a port.
  
  @param request
  @param page
  @return