added many to many relation

src/main/java/ntnu/idatt2016/v233/SmartMat/entity/ShoppingList.java

 package ntnu.idatt2016.v233.SmartMat.entity;
 
 
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import jakarta.persistence.*;
 import lombok.AllArgsConstructor;
 import lombok.Builder;
 import lombok.Data;
 import lombok.NoArgsConstructor;
+import ntnu.idatt2016.v233.SmartMat.entity.product.Product;
+
+import java.util.List;
 
 /**
  * This class represents a shopping list
@@ -29,4 +33,13 @@ public class ShoppingList {
 
     @Column(name = "group_id")
     long groupID;
+
+    @ManyToMany
+    @JoinTable(
+            name = "shopping_list_product",
+            joinColumns = @JoinColumn(name = "shopping_list_id"),
+            inverseJoinColumns = @JoinColumn(name = "ean"))
+    @JsonIgnoreProperties("shoppingList")
+    private List<Product> products;
+
 }

src/main/java/ntnu/idatt2016/v233/SmartMat/entity/product/Product.java

@@ -7,6 +7,7 @@ import lombok.AllArgsConstructor;
 import lombok.Builder;
 import lombok.Data;
 import lombok.NoArgsConstructor;
+import ntnu.idatt2016.v233.SmartMat.entity.ShoppingList;
 import ntnu.idatt2016.v233.SmartMat.entity.group.Fridge;
 import ntnu.idatt2016.v233.SmartMat.entity.Recipe;
 import ntnu.idatt2016.v233.SmartMat.entity.fridgeProduct.FridgeProductAsso;
@@ -36,6 +37,10 @@ public class Product{
     @Column(name = "description")
     String description;
 
+    @ManyToMany(mappedBy = "products")
+    @JsonIgnoreProperties({"products"})
+    List<ShoppingList> shoppingLists;
+
 
     @ManyToOne
     @JoinColumn(name = "category_name")

src/main/java/ntnu/idatt2016/v233/SmartMat/service/ShoppingListService.java

@@ -3,6 +3,7 @@ package ntnu.idatt2016.v233.SmartMat.service;
 import java.util.List;
 import java.util.Optional;
 
+import ntnu.idatt2016.v233.SmartMat.entity.product.Product;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 
@@ -74,4 +75,9 @@ public class ShoppingListService {
             shoppingListRepository.deleteById(id);
         }
     }
+
+    public Product addProductToShoppingList(long ean, long shoppingListId){
+        return null;
+    }
+
 }