code: private void doGetUpdate() throws PageException {
  	Struct sct = new StructImpl();
  	pageContext.setVariable(getString("admin", action, "returnVariable"), sct);
  	URL location = config.getUpdateLocation();
  	if (location == null) location = Constants.DEFAULT_UPDATE_URL;
  
  	String type = config.getUpdateType();
  	if (StringUtil.isEmpty(type)) type = "manual";
  
  	sct.set("location", location.toExternalForm());
  	sct.set("type", type);
  
      }
docs: @throws PageException