public static boolean isUIRepeat(UIComponent component) {
        return component.getClass().getName().endsWith("UIRepeat");
    }
Execute a callback in a stateless scope by temporarily removing and restoring a variable from the FacesContext attributes.

@param context The FacesContext used for accessing attributes
@param var The variable to be temporarily removed and restored in the context attributes
@param runnable The callback to be executed
@param <E> The type of Throwable that may be thrown
@throws E If the callback throws an exception of type E
primefaces/src/main/java/org/primefaces/util/ComponentUtils.java