<?php

// No direct access
defined('_JEXEC'  ) or die('Restricted access');

$app = JFactory::getApplication();
$id = $app->input->getInt('id');
// get product
$product = F0FTable::getAnInstance('Product', 'J2StoreTable')->getClone();
// get product variant
$variant = F0FTable::getAnInstance('Variant','J2StoreTable');
$variant->load(array('product_id' => $id));
// get article
$article = JTable::getInstance('content');

// ARTICLE ID IS NOT ALWAYS EQUAL TO PRODUCT ID, DEPENDS IF WE ARE IN COM_CONTENT OR COM_J2STORE
$article->load($id);

if($product->get_product_by_source('com_content', $id)) {
	// get data from #__j2store_products table (main_image, thumb_image, additional_images, up_sells, cross_sells, manufacturer)
	echo $product->main_image;
	// get data from #__j2store_variants table (sku, price, dimensions...)
	echo $variant->sku;
	// get data from #__com_content table
	echo $article->get('title');
}