feat(catalog): categories and products

README.md

@@ -401,11 +401,11 @@ Full CRUD for users, roles, and permissions, still inside `core/auth`. Assignmen
 
 ### Tasks
 
-- [ ] `core/catalog`: `Category`, `Product` entity classes (`@Table("categories")`/`@Table("products")`) and `CategoryDto`/`ProductDto`, `CategoryRowMapper`/`ProductRowMapper` (entity) plus `CategoryMapper`/`ProductMapper` (entity ↔ dto), `CategoryDao`/`ProductDao` + impl, `CategoryService`/`ProductService` + impl, `DaoConfig`/`ServiceConfig`
-- [ ] Business rule: deleting a category that still has products is rejected (`BusinessRuleException` → 422)
-- [ ] `ws`: `CategoryController`, `ProductController`, `CategoryConverter`, `ProductConverter`
-- [ ] `WebMvcConfig` updated to import `core/catalog`'s config
-- [ ] Tests at all five layers - `CategoryDao`/`ProductDao` each with their own fixture dataset, the category-deletion rejection case, a permission-denied case
+- [x] `core/catalog`: `Category`, `Product` entity classes (`@Table("categories")`/`@Table("products")`) and `CategoryDto`/`ProductDto`, `CategoryRowMapper`/`ProductRowMapper` (entity) plus `CategoryMapper`/`ProductMapper` (entity ↔ dto), `CategoryDao`/`ProductDao` + impl, `CategoryService`/`ProductService` + impl, `DaoConfig`/`ServiceConfig`
+- [x] Business rule: deleting a category that still has products is rejected (`BusinessRuleException` → 422)
+- [x] `ws`: `CategoryController`, `ProductController`, `CategoryConverter`, `ProductConverter`
+- [x] `WebMvcConfig` updated to import `core/catalog`'s config
+- [x] Tests at all five layers - `CategoryDao`/`ProductDao` each with their own fixture dataset, the category-deletion rejection case, a permission-denied case
 
 ## feature/customer
 

core/catalog/pom.xml

@@ -19,5 +19,22 @@
             <groupId>com.edgareldy.springjdbctutorial</groupId>
             <artifactId>common</artifactId>
         </dependency>
+        <!-- Test scope only: the DAO tests reuse the PostgreSQL Testcontainer support published by common -->
+        <dependency>
+            <groupId>com.edgareldy.springjdbctutorial</groupId>
+            <artifactId>common</artifactId>
+            <type>test-jar</type>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>postgresql</artifactId>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 </project>

core/catalog/src/main/java/com/edgareldy/springjdbctutorial/core/catalog/config/DaoConfig.java

@@ -0,0 +1,31 @@
+package com.edgareldy.springjdbctutorial.core.catalog.config;
+
+import com.edgareldy.springjdbctutorial.core.catalog.dao.CategoryDao;
+import com.edgareldy.springjdbctutorial.core.catalog.dao.ProductDao;
+import com.edgareldy.springjdbctutorial.core.catalog.dao.impl.CategoryDaoImpl;
+import com.edgareldy.springjdbctutorial.core.catalog.dao.impl.ProductDaoImpl;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+/**
+ * Declares the DAO beans of the catalog module, typed by interface (no stereotype on the implementations).
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+@Configuration
+public class DaoConfig {
+
+    @Bean
+    public CategoryDao categoryDao(JdbcTemplate jdbcTemplate) {
+        return new CategoryDaoImpl(jdbcTemplate);
+    }
+
+    @Bean
+    public ProductDao productDao(JdbcTemplate jdbcTemplate) {
+        return new ProductDaoImpl(jdbcTemplate);
+    }
+}

core/catalog/src/main/java/com/edgareldy/springjdbctutorial/core/catalog/config/ServiceConfig.java

@@ -0,0 +1,34 @@
+package com.edgareldy.springjdbctutorial.core.catalog.config;
+
+import com.edgareldy.springjdbctutorial.core.catalog.dao.CategoryDao;
+import com.edgareldy.springjdbctutorial.core.catalog.dao.ProductDao;
+import com.edgareldy.springjdbctutorial.core.catalog.service.CategoryService;
+import com.edgareldy.springjdbctutorial.core.catalog.service.ProductService;
+import com.edgareldy.springjdbctutorial.core.catalog.service.impl.CategoryServiceImpl;
+import com.edgareldy.springjdbctutorial.core.catalog.service.impl.ProductServiceImpl;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+
+/**
+ * Declares the service beans of the catalog module. Imports its DaoConfig so importing this class alone is enough.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+@Configuration
+@Import(DaoConfig.class)
+public class ServiceConfig {
+
+    @Bean
+    public CategoryService categoryService(CategoryDao categoryDao, ProductDao productDao) {
+        return new CategoryServiceImpl(categoryDao, productDao);
+    }
+
+    @Bean
+    public ProductService productService(ProductDao productDao, CategoryDao categoryDao) {
+        return new ProductServiceImpl(productDao, categoryDao);
+    }
+}

core/catalog/src/main/java/com/edgareldy/springjdbctutorial/core/catalog/dao/CategoryDao.java

@@ -0,0 +1,33 @@
+package com.edgareldy.springjdbctutorial.core.catalog.dao;
+
+import com.edgareldy.springjdbctutorial.core.catalog.entity.Category;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Data access for categories. Entity types only.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+public interface CategoryDao {
+
+    /** One page of categories ordered by id. */
+    List<Category> findPage(int page, int size);
+
+    long countAll();
+
+    Optional<Category> findById(Long id);
+
+    boolean existsByCategoryName(String categoryName);
+
+    /** Inserts the category and returns it with its generated id. */
+    Category insert(Category category);
+
+    void update(Category category);
+
+    void delete(Long id);
+}

core/catalog/src/main/java/com/edgareldy/springjdbctutorial/core/catalog/dao/ProductDao.java

@@ -0,0 +1,34 @@
+package com.edgareldy.springjdbctutorial.core.catalog.dao;
+
+import com.edgareldy.springjdbctutorial.core.catalog.entity.Product;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Data access for products. Entity types only.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+public interface ProductDao {
+
+    /** One page of products ordered by id, restricted to a category when categoryId is not null. */
+    List<Product> findPage(int page, int size, Long categoryId);
+
+    /** Number of products, restricted to a category when categoryId is not null. */
+    long count(Long categoryId);
+
+    Optional<Product> findById(Long id);
+
+    /** Inserts the product and returns it with its generated id. */
+    Product insert(Product product);
+
+    void update(Product product);
+
+    void delete(Long id);
+
+    long countByCategoryId(Long categoryId);
+}

core/catalog/src/main/java/com/edgareldy/springjdbctutorial/core/catalog/dao/impl/CategoryDaoImpl.java

@@ -0,0 +1,68 @@
+package com.edgareldy.springjdbctutorial.core.catalog.dao.impl;
+
+import com.edgareldy.springjdbctutorial.core.catalog.dao.CategoryDao;
+import com.edgareldy.springjdbctutorial.core.catalog.entity.Category;
+import com.edgareldy.springjdbctutorial.core.catalog.mapper.CategoryRowMapper;
+import com.edgareldy.springjdbctutorial.core.common.dao.support.AbstractDao;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * JdbcTemplate implementation of CategoryDao. Declared by @Bean in DaoConfig, no stereotype.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+public class CategoryDaoImpl extends AbstractDao implements CategoryDao {
+
+    private final CategoryRowMapper rowMapper = new CategoryRowMapper();
+
+    public CategoryDaoImpl(JdbcTemplate jdbcTemplate) {
+        super(jdbcTemplate);
+    }
+
+    @Override
+    public List<Category> findPage(int page, int size) {
+        return getJdbcTemplate().query(
+                "SELECT id, category_name FROM categories ORDER BY id LIMIT ? OFFSET ?",
+                rowMapper, size, (long) page * size);
+    }
+
+    @Override
+    public long countAll() {
+        return count("SELECT COUNT(*) FROM categories");
+    }
+
+    @Override
+    public Optional<Category> findById(Long id) {
+        return findOne("SELECT id, category_name FROM categories WHERE id = ?", rowMapper, id);
+    }
+
+    @Override
+    public boolean existsByCategoryName(String categoryName) {
+        return count("SELECT COUNT(*) FROM categories WHERE category_name = ?", categoryName) > 0;
+    }
+
+    @Override
+    public Category insert(Category category) {
+        long id = insertReturningId("INSERT INTO categories (category_name) VALUES (?) RETURNING id",
+                category.getCategoryName());
+        category.setId(id);
+        return category;
+    }
+
+    @Override
+    public void update(Category category) {
+        getJdbcTemplate().update("UPDATE categories SET category_name = ? WHERE id = ?",
+                category.getCategoryName(), category.getId());
+    }
+
+    @Override
+    public void delete(Long id) {
+        getJdbcTemplate().update("DELETE FROM categories WHERE id = ?", id);
+    }
+}

core/catalog/src/main/java/com/edgareldy/springjdbctutorial/core/catalog/dao/impl/ProductDaoImpl.java

@@ -0,0 +1,78 @@
+package com.edgareldy.springjdbctutorial.core.catalog.dao.impl;
+
+import com.edgareldy.springjdbctutorial.core.catalog.dao.ProductDao;
+import com.edgareldy.springjdbctutorial.core.catalog.entity.Product;
+import com.edgareldy.springjdbctutorial.core.catalog.mapper.ProductRowMapper;
+import com.edgareldy.springjdbctutorial.core.common.dao.support.AbstractDao;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * JdbcTemplate implementation of ProductDao. Declared by @Bean in DaoConfig, no stereotype.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+public class ProductDaoImpl extends AbstractDao implements ProductDao {
+
+    private static final String COLUMNS = "SELECT id, category_id, product_name, unit_price FROM products";
+
+    private final ProductRowMapper rowMapper = new ProductRowMapper();
+
+    public ProductDaoImpl(JdbcTemplate jdbcTemplate) {
+        super(jdbcTemplate);
+    }
+
+    @Override
+    public List<Product> findPage(int page, int size, Long categoryId) {
+        long offset = (long) page * size;
+        if (categoryId == null) {
+            return getJdbcTemplate().query(COLUMNS + " ORDER BY id LIMIT ? OFFSET ?", rowMapper, size, offset);
+        }
+        return getJdbcTemplate().query(COLUMNS + " WHERE category_id = ? ORDER BY id LIMIT ? OFFSET ?",
+                rowMapper, categoryId, size, offset);
+    }
+
+    @Override
+    public long count(Long categoryId) {
+        if (categoryId == null) {
+            return count("SELECT COUNT(*) FROM products");
+        }
+        return countByCategoryId(categoryId);
+    }
+
+    @Override
+    public Optional<Product> findById(Long id) {
+        return findOne(COLUMNS + " WHERE id = ?", rowMapper, id);
+    }
+
+    @Override
+    public Product insert(Product product) {
+        long id = insertReturningId(
+                "INSERT INTO products (category_id, product_name, unit_price) VALUES (?, ?, ?) RETURNING id",
+                product.getCategoryId(), product.getProductName(), product.getUnitPrice());
+        product.setId(id);
+        return product;
+    }
+
+    @Override
+    public void update(Product product) {
+        getJdbcTemplate().update(
+                "UPDATE products SET category_id = ?, product_name = ?, unit_price = ? WHERE id = ?",
+                product.getCategoryId(), product.getProductName(), product.getUnitPrice(), product.getId());
+    }
+
+    @Override
+    public void delete(Long id) {
+        getJdbcTemplate().update("DELETE FROM products WHERE id = ?", id);
+    }
+
+    @Override
+    public long countByCategoryId(Long categoryId) {
+        return count("SELECT COUNT(*) FROM products WHERE category_id = ?", categoryId);
+    }
+}

core/catalog/src/main/java/com/edgareldy/springjdbctutorial/core/catalog/dto/CategoryDto.java

@@ -0,0 +1,67 @@
+package com.edgareldy.springjdbctutorial.core.catalog.dto;
+
+import java.util.Objects;
+
+/**
+ * Business shape of a category.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+public class CategoryDto {
+
+    private Long id;
+
+    private String categoryName;
+
+    public CategoryDto() {
+    }
+
+    public CategoryDto(Long id, String categoryName) {
+        this.id = id;
+        this.categoryName = categoryName;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getCategoryName() {
+        return categoryName;
+    }
+
+    public void setCategoryName(String categoryName) {
+        this.categoryName = categoryName;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        CategoryDto that = (CategoryDto) o;
+        return Objects.equals(id, that.id) && Objects.equals(categoryName, that.categoryName);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(id, categoryName);
+    }
+
+    @Override
+    public String toString() {
+        return "CategoryDto{" +
+                "id=" + id +
+                ", categoryName=" + categoryName +
+                "}";
+    }
+}