public void apply(FaceletContext ctx, UIComponent parent) throws IOException { // only process if it's been created if (parent == null || !ComponentHandler.isNew(parent)) { return; } if (isEventSource(parent)) { applyAttachedObject(ctx.getFacesContext(), parent); } else if (UIComponent.isCompositeComponent(parent)) { // Allow the composite component to know about the target component. TagHandlerUtils.getOrCreateRetargetableHandlersList(parent).add(this); } else { throw new TagException( this.tag, "Parent does not match event source requirements: " + parent); } }