Controller
------------------->
try {
		// See whether this product can be shown on PDP
		ProductHelper.canDisplayProductPDP(httpParameterMap, productModel);
	} catch (e) {
		// If redirectUrl is set by canDisplayProductPDP()
		if (!empty(ProductHelper.getRedirectUrl())) {
			response.redirect(ProductHelper.getRedirectUrl());
			return;
		}

		// In case a pipeline is called by canDisplayProductPDP() and it renders a template or redirects execution to
		// another pipeline that will render a template then just return
		if (ProductHelper.getIsRenderedByPipeline()) {
			return;
		}

		// Throw and error because something unhandled happened
		throw e;
	}
---------------->

Helper
---------------->
ProductHelper.canDisplayProductPDP = function (httpParameterMap, productModel) {
	if (!SitePreference.get('v3_pdp_redesign_enabled')) {
		this.callBundlesQuickviewHook();
	}
	// Please note that handleOfflineProduct and handlePDPForbiddenProduct methods cover the ProductHelper-CheckGWP pipeline functionality
	this.handleOfflineProduct(productModel);
	this.handlePDPForbiddenProduct(httpParameterMap, productModel);
	this.handlePermanentOutOfStockProduct(productModel);
	this.handleOfflineProductSet(productModel);
};

ProductHelper.handleOfflineProduct = function(productModel) {
	if (!productModel.exec('isOnline')) {
		this.redirectUrl = URLUtils.url('Home-Show');

		var catalogCategory = productModel.exec('getDerivedOnlineCategoryId');
		if (!empty(catalogCategory)) {
			this.redirectUrl = URLUtils.url('Search-Show', 'cgid', catalogCategory);
		}

		throw new Exception('Offline product redirect to URL ' + this.redirectUrl, true , '', Exception.ERROR_CODE_OFFLINE_PRODUCT_REDIRECT, false);
	}
};

ProductHelper.handlePDPForbiddenProduct = function(httpParameterMap, productModel) {
	var isSourceBundle = (httpParameterMap.isParameterSubmitted('source') && httpParameterMap.source.stringValue === 'bundle');
	var isAjax = (httpParameterMap.isParameterSubmitted('format') && httpParameterMap.format.stringValue === 'ajax');
	var isQuickViewAndTrial = isSourceBundle && isAjax && productModel.exec('isTrial');

	var dontShowBundlePage = (!SitePreference.get('v3_pdp_bundle_page_enabled') && productModel.exec('isBundle')) || productModel.exec('isSamplesRoutineBundle');

	var incompatible = productModel.exec('isSample') || productModel.exec('isTrial')
				|| productModel.exec('getCustom', 'isFree') || productModel.exec('isGiftWrap')
				|| productModel.exec('isHidden') || dontShowBundlePage || isQuickViewAndTrial;

	if (incompatible) {
		this.redirectUrl = URLUtils.url('Error-Start');
		throw new Exception("PDP not available for this product id " + productModel.exec('getId'), true, '', Exception.ERROR_PRODUCT_SHOW_NOT_AVAILABLE, false);
	}
};