ProductRepository extends JpaRepository

PC27-SklepSpring/src/main/java/sklep/controller/ProductController.java

@@ -8,28 +8,30 @@ import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestMapping;
 import sklep.model.Product;
+import sklep.repository.ProductRepository;
 
 import java.util.List;
+import java.util.Optional;
 
 
 @Controller
 @RequestMapping("/products")
 public class ProductController {
     @Autowired
-    private EntityManager em;
+    private ProductRepository productRepository;
 
     @GetMapping
     public String readAll(Model model) {
-        List<Product> products = em.createNamedQuery("Product.findAll", Product.class).getResultList();
+        List<Product> products = productRepository.findAll();
         model.addAttribute("products", products);
         return "products";
     }
 
     @GetMapping("/{id}")
     public String readOne(@PathVariable("id") Integer productId, Model model) {
-        Product product = em.find(Product.class, productId);
-        if(product != null) {
-            model.addAttribute("product", product);
+        Optional<Product> product = productRepository.findById(productId);
+        if(product.isPresent()) {
+            model.addAttribute("product", product.get());
             return "product";
         } else {
             return "missing_product";

PC27-SklepSpring/src/main/java/sklep/repository/ProductRepository.java

+package sklep.repository;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import sklep.model.Product;
+
+public interface ProductRepository extends JpaRepository<Product, Integer> {
+}