code: public void addTarget(final AjaxTarget target) {
  		AjaxControlModel model = getOrCreateComponentModel();
  
  		if (model.targets == null) {
  			model.targets = new ArrayList<>();
  		}
  
  		model.targets.add(target);
  		MemoryUtil.checkSize(model.targets.size(), this.getClass().getSimpleName());
  	}
docs: Add a single target WComponent to this AJAX control.
  
  @param target a WComponent to be repainted