code: public static AjaxOperation getAjaxOperation(final String triggerId) {
  		Map<String, AjaxOperation> operations = getRegisteredOperations();
  		return operations == null ? null : operations.get(triggerId);
  	}
docs: Retrieves the AjaxOperation that has been registered for the given trigger. This method will return null if there
  is no corresponding operation registered.
  
  @param triggerId the trigger id.
  @return the AjaxOperation corresponding to the trigger id.