As far as I got

pom.xml

@@ -67,6 +67,11 @@
                 </exclusion>
             </exclusions>
         </dependency>
+        <dependency>
+            <groupId>org.sonatype.sisu</groupId>
+            <artifactId>sisu-inject-bean</artifactId>
+            <version>1.4.2</version>
+        </dependency>
 
     </dependencies>
 

src/main/java/com/dtcc/projects/productcategories/controllers/AssociationController.java

@@ -1,4 +1,41 @@
-package com.dtcc.projects.productcategories.controllers;
+import com.dtcc.projects.productcategories.models.Association;
+import com.dtcc.projects.productcategories.models.Product;
+import com.dtcc.projects.productcategories.services.AssociationService;
+import com.dtcc.projects.productcategories.services.ProductService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
 
+import java.util.List;
+
+@Controller
 public class AssociationController {
+
+
+    @Autowired
+    private AssociationService associationService;
+    @Autowired
+    private ProductService productService;
+
+
+    @RequestMapping(value="/associations/products",method=RequestMethod.POST)
+    public String setCategoriesProducts(Model model, @ModelAttribute("association") Association association){
+        List<Product>productList = productService.showAll();
+        model.addAttribute("products",productList);
+
+        //save data into categories_products table.
+        associationService.saveAssociation(association);
+        return "/products/index";
+    }
+
+//    @RequestMapping(value="/associations/categories",method=RequestMethod.POST)
+//    public String getCategory(Model model, @ModelAttribute("association1") Association associationObj){
+//        List<Product> productList =  productService.showAll();
+//        model.addAttribute("products",productList);
+//        associationService.saveAssociation(associationObj);
+//        return "/products/index";
+//    }
 }

src/main/java/com/dtcc/projects/productcategories/controllers/CategoryController.java

@@ -0,0 +1,61 @@
+package com.dtcc.projects.productcategories.controllers;
+
+import com.dtcc.projects.productcategories.models.Association;
+import com.dtcc.projects.productcategories.models.Category;
+import com.dtcc.projects.productcategories.models.Product;
+import com.dtcc.projects.productcategories.services.CategoryService;
+import com.dtcc.projects.productcategories.services.ProductService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.Date;
+import java.util.List;
+@Controller
+public class CategoryController {
+    @Autowired
+    private CategoryService categoryService;
+    @Autowired ProductService productService;
+
+    @GetMapping(value = "/categories/category")
+    public String getCategoryIndex(Model model){
+        List<Category> categoryList = categoryService.showAll();
+        model.addAttribute("categories", categoryList);
+        return "categories/categoriesindex";
+    }
+
+    @GetMapping(value = "/categories/newcategory")
+    public String newcat(Model model){
+        model.addAttribute("newcategory", new Category());
+        return "categories/newcategory";
+    }
+
+    @PostMapping(value = "/categories/createcategory")
+    public String createCategory(@ModelAttribute("newcategory")Category cat){
+        List<Category> temp = categoryService.showAll();
+        cat.setCreated_at(new Date());
+        boolean exists = false;
+        for(Category c:temp){
+            if(c.getValue().equals(cat.getValue())){
+                exists = true;
+            }
+        }
+        if(!exists){
+            categoryService.saveCategory(cat);
+        }
+        return "redirect:/";
+    }
+
+//    @RequestMapping(value="categories/{id}",method= RequestMethod.GET)
+//    public String showById(Model model, @PathVariable Integer id){
+//        Category category=categoryService.findById(id);
+//        List<Product> productList= productService.findByCategoriesNotContains(category);
+//
+//        Association association =new Association();
+//        model.addAttribute("category",category);
+//        model.addAttribute("association",association);
+//        model.addAttribute("notInProducts",productList);
+//        return "categories/show";
+//    }
+}

src/main/java/com/dtcc/projects/productcategories/controllers/ProductController.java

@@ -1,4 +1,67 @@
 package com.dtcc.projects.productcategories.controllers;
 
-public class ProductController {
+import com.dtcc.projects.productcategories.models.Association;
+import com.dtcc.projects.productcategories.models.Category;
+import com.dtcc.projects.productcategories.models.Product;
+import com.dtcc.projects.productcategories.services.CategoryService;
+import com.dtcc.projects.productcategories.services.ProductService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.Date;
+import java.util.List;
+
+@Controller
+public class ProductController{
+
+    @Autowired
+    private ProductService productService;
+    @Autowired
+    private CategoryService categoryService;
+
+    @GetMapping(value = "/")
+    public String getIndexPage(Model model){
+        List<Product> prdocutList = productService.showAll();
+        model.addAttribute("products", prdocutList);
+        return "products/index";
+    }
+
+    @GetMapping("/products/newproduct")//.jsp file location/name
+    public String newprod(Model model) {
+        model.addAttribute("newproduct", new Product()); //Creating and inserting in JSp
+
+        return "products/newproduct";//Returns .jsp page
+    }
+
+    @PostMapping(value = "/products/createproduct") //the action clause
+    public String createProduct(@ModelAttribute("newproduct") Product item){//action attribute
+        List<Product> temp = productService.showAll();
+        item.setCreated_at(new Date());
+        productService.saveProduct(item);
+
+        for(Product p:temp) {
+            if(p.getProductName().equals(item.getProductName())){
+                productService.updateProduct(p.getProductId(), item.getProductName(),item.getDescription(), item.getPrice());
+                p.setUpdated_at(new Date());
+                productService.saveProduct(p);
+                productService.deleteById(item.getProductId());
+            }
+        }
+
+        return "redirect:/";//Go back to main page
+    }
+
+//    @RequestMapping(value="products/{id}",method=RequestMethod.GET)
+//    public String showById(Model model,@PathVariable Integer id){
+//        Product product = productService.findById(id);
+//        List<Category> categoryList = categoryService.findByProductsNotContains(product);
+//        Association association = new Association();
+//
+//        model.addAttribute("product",product);
+//        model.addAttribute("association",association);
+//        model.addAttribute("notInCategories",categoryList);
+//        return "products/show";
+//    }
 }

src/main/java/com/dtcc/projects/productcategories/models/Association.java

@@ -1,4 +1,38 @@
 package com.dtcc.projects.productcategories.models;
 
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import javax.persistence.*;
+import java.util.Date;
+import java.util.List;
+
+@Data
+@Entity
+@NoArgsConstructor
+@Table(name = "categories_products")
 public class Association {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "PRODUCT_ID")
+    private Product productId;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "CATEGORY_ID")
+    private Category categoryId;
+
+    @Column(name = "CREATED_AT")
+    private Date createdAt;
+
+    @Column(name = "UPDATED_AT")
+    private Date updatedAt;
+
+    public Association(Product productId, Category categoryId) {
+        this.productId = productId;
+        this.categoryId = categoryId;
+    }
 }

src/main/java/com/dtcc/projects/productcategories/models/Category.java

@@ -1,4 +1,38 @@
 package com.dtcc.projects.productcategories.models;
 
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import javax.persistence.*;
+import java.util.Date;
+import java.util.List;
+
+@Data
+@Entity
+@NoArgsConstructor
 public class Category {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    @Column(name = "CATEGORY_ID")
+    private Integer categoryId;
+
+    @Column(name = "CATEGORY_NAME")
+    private String value;
+
+    @Column(name = "CREATED_AT")
+    private Date created_at;
+
+    @Column(name = "UPDATED_AT")
+    private Date updated_at;
+
+    @ManyToMany
+    @JoinTable(name = "categories_products", joinColumns = @JoinColumn(name = "category_id"), inverseJoinColumns = @JoinColumn(name = "product_id"))
+    private List<Product> productList;
+
+    public Category(String value, Date created_at, Date updated_at) {
+        this.value = value;
+        this.created_at = created_at;
+        this.updated_at = updated_at;
+    }
 }

src/main/java/com/dtcc/projects/productcategories/models/Product.java

@@ -1,4 +1,48 @@
 package com.dtcc.projects.productcategories.models;
 
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import javax.persistence.*;
+import java.time.LocalDate;
+import java.util.Date;
+import java.util.List;
+
+@Data
+@Entity
+@NoArgsConstructor
 public class Product {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    @Column(name = "PRODUCT_ID")
+    private Integer productId;
+
+    @Column(name = "PRDOCUT_NAME")
+    private String productName;
+
+    @Column(name = "DESCRIPTION")
+    private String description;
+
+    @Column(name = "PRICE")
+    private Double price;
+
+    @Column(name = "CREATED_AT")
+    private Date created_at;
+
+    @Column(name = "UPDATED_AT")
+    private Date updated_at;
+
+    @ManyToMany
+    @JoinTable(name = "categories_products", joinColumns = @JoinColumn(name = "product_id"), inverseJoinColumns = @JoinColumn(name = "category_id"))
+    private List<Category> categoryList;
+
+    public Product(String productName, String description, Double price, Date created_at, Date updated_at) {
+        this.productName = productName;
+        this.description = description;
+        this.price = price;
+        this.created_at = created_at;
+        this.updated_at = updated_at;
+    }
+
 }

src/main/java/com/dtcc/projects/productcategories/repositories/AssociationRepository.java

@@ -1,4 +1,11 @@
 package com.dtcc.projects.productcategories.repositories;
 
-public interface AssociationRepository {
+import com.dtcc.projects.productcategories.models.Association;
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.stereotype.Repository;
+
+
+@Repository
+public interface AssociationRepository extends CrudRepository<Association,Long> {
+
 }

src/main/java/com/dtcc/projects/productcategories/repositories/CategoryRepository.java

@@ -1,8 +1,15 @@
 package com.dtcc.projects.productcategories.repositories;
 
+import com.dtcc.projects.productcategories.models.Category;
+import com.dtcc.projects.productcategories.models.Product;
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.stereotype.Repository;
+
 import java.util.List;
 
-public interface CategoryRepository {
+@Repository
+public interface CategoryRepository extends CrudRepository<Category, Integer> {
     List<Category> findAll();
-    List<Category> findByProductsNotContains(Product product);
+   // List<Category> findByProductsNotContains(Product product);
+
 }

src/main/java/com/dtcc/projects/productcategories/repositories/ProductRepository.java

@@ -1,8 +1,14 @@
 package com.dtcc.projects.productcategories.repositories;
 
+import com.dtcc.projects.productcategories.models.Category;
+import com.dtcc.projects.productcategories.models.Product;
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.stereotype.Repository;
+
 import java.util.List;
 
-public interface ProductRepository {
+@Repository
+public interface ProductRepository extends CrudRepository<Product, Integer> {
     List<Product> findAll();
-    List<Product> findByCategoriesNotContains(Category category);
+    //List<Product> findByCategoriesNotContains(Category category);
 }

src/main/java/com/dtcc/projects/productcategories/services/AssociationService.java

@@ -0,0 +1,21 @@
+package com.dtcc.projects.productcategories.services;
+
+import com.dtcc.projects.productcategories.models.Association;
+import com.dtcc.projects.productcategories.repositories.AssociationRepository;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+@Service
+public class AssociationService {
+
+    private AssociationRepository associationRepository;
+
+    @Autowired
+    public AssociationService(AssociationRepository associationRepository){
+        this.associationRepository = associationRepository;
+    }
+
+    public Association saveAssociation(Association association){
+        return associationRepository.save(association);
+    }
+}