feat(order): orders computed from catalog prices

README.md

@@ -209,7 +209,7 @@ spring-jdbc-tutorial/
 │           ├── dto/ (OrderDto.java)
 │           ├── mapper/ (OrderRowMapper.java, OrderMapper.java)
 │           ├── dao/ (OrderDao.java + impl/)
-│           ├── service/ (OrderService.java + impl/, depends on CategoryService/ProductService/CustomerService)
+│           ├── service/ (OrderService.java + impl/, depends on ProductService/CustomerService only: the category is never needed)
 │           └── config/ (DaoConfig.java, ServiceConfig.java)
 └── ws/
     ├── pom.xml                                    (depends on core/auth, core/catalog, core/customer, core/order)
@@ -438,11 +438,11 @@ Full CRUD for users, roles, and permissions, still inside `core/auth`. Assignmen
 
 ### Tasks
 
-- [ ] `core/order`: `Order` entity (`@Table("orders")`) and `OrderDto`, `OrderRowMapper` (entity) plus `OrderMapper` (entity ↔ dto), `OrderDao` + impl, `OrderService` + impl (depends on `catalog`'s `ProductService` and `customer`'s `CustomerService` - their service interfaces, never their DAOs directly): computes `total = quantity * product.unitPrice`, checks the referenced customer/product exist
-- [ ] `core/order`'s `DaoConfig`/`ServiceConfig` (the latter injecting `ProductService`/`CustomerService` beans from the other modules' contexts)
-- [ ] `ws`: `OrderController`, `OrderConverter`
-- [ ] `WebMvcConfig` updated to import `core/order`'s config
-- [ ] Tests at all five layers, `OrderDao` with its own fixture dataset, the total computation, and the not-found cases for a bad `customerId`/`productId`
+- [x] `core/order`: `Order` entity (`@Table("orders")`) and `OrderDto`, `OrderRowMapper` (entity) plus `OrderMapper` (entity ↔ dto), `OrderDao` + impl, `OrderService` + impl (depends on `catalog`'s `ProductService` and `customer`'s `CustomerService` - their service interfaces, never their DAOs directly): computes `total = quantity * product.unitPrice`, checks the referenced customer/product exist
+- [x] `core/order`'s `DaoConfig`/`ServiceConfig` (the latter injecting `ProductService`/`CustomerService` beans from the other modules' contexts)
+- [x] `ws`: `OrderController`, `OrderConverter`
+- [x] `WebMvcConfig` updated to import `core/order`'s config
+- [x] Tests at all five layers, `OrderDao` with its own fixture dataset, the total computation, and the not-found cases for a bad `customerId`/`productId`
 
 ## Order of work
 

core/order/pom.xml

@@ -23,5 +23,22 @@
             <groupId>com.edgareldy.springjdbctutorial</groupId>
             <artifactId>customer</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/order/src/main/java/com/edgareldy/springjdbctutorial/core/order/config/DaoConfig.java

@@ -0,0 +1,24 @@
+package com.edgareldy.springjdbctutorial.core.order.config;
+
+import com.edgareldy.springjdbctutorial.core.order.dao.OrderDao;
+import com.edgareldy.springjdbctutorial.core.order.dao.impl.OrderDaoImpl;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+/**
+ * Declares the DAO beans of the order 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 OrderDao orderDao(JdbcTemplate jdbcTemplate) {
+        return new OrderDaoImpl(jdbcTemplate);
+    }
+}

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

@@ -0,0 +1,31 @@
+package com.edgareldy.springjdbctutorial.core.order.config;
+
+import com.edgareldy.springjdbctutorial.core.catalog.service.ProductService;
+import com.edgareldy.springjdbctutorial.core.customer.service.CustomerService;
+import com.edgareldy.springjdbctutorial.core.order.dao.OrderDao;
+import com.edgareldy.springjdbctutorial.core.order.service.OrderService;
+import com.edgareldy.springjdbctutorial.core.order.service.impl.OrderServiceImpl;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Import;
+
+/**
+ * Declares the service beans of the order module. Imports its DaoConfig and the catalog and customer
+ * ServiceConfig (fully qualified, every module has a class of that name) 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,
+        com.edgareldy.springjdbctutorial.core.catalog.config.ServiceConfig.class,
+        com.edgareldy.springjdbctutorial.core.customer.config.ServiceConfig.class})
+public class ServiceConfig {
+
+    @Bean
+    public OrderService orderService(OrderDao orderDao, ProductService productService, CustomerService customerService) {
+        return new OrderServiceImpl(orderDao, productService, customerService);
+    }
+}

core/order/src/main/java/com/edgareldy/springjdbctutorial/core/order/dao/OrderDao.java

@@ -0,0 +1,28 @@
+package com.edgareldy.springjdbctutorial.core.order.dao;
+
+import com.edgareldy.springjdbctutorial.core.order.entity.Order;
+
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Data access for orders. Entity types only. Orders are immutable: there is no update and no delete.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+public interface OrderDao {
+
+    /** One page of orders ordered by id, each filter is applied only when not null. */
+    List<Order> findPage(int page, int size, Long customerId, Long productId);
+
+    /** Number of orders matching the same optional filters. */
+    long count(Long customerId, Long productId);
+
+    Optional<Order> findById(Long id);
+
+    /** Inserts the order and returns it with its generated id. */
+    Order insert(Order order);
+}

core/order/src/main/java/com/edgareldy/springjdbctutorial/core/order/dao/impl/OrderDaoImpl.java

@@ -0,0 +1,78 @@
+package com.edgareldy.springjdbctutorial.core.order.dao.impl;
+
+import com.edgareldy.springjdbctutorial.core.common.dao.support.AbstractDao;
+import com.edgareldy.springjdbctutorial.core.order.dao.OrderDao;
+import com.edgareldy.springjdbctutorial.core.order.entity.Order;
+import com.edgareldy.springjdbctutorial.core.order.mapper.OrderRowMapper;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * JdbcTemplate implementation of OrderDao. 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 OrderDaoImpl extends AbstractDao implements OrderDao {
+
+    private static final String SELECT = "SELECT id, customer_id, product_id, quantity, total FROM orders";
+
+    private final OrderRowMapper rowMapper = new OrderRowMapper();
+
+    public OrderDaoImpl(JdbcTemplate jdbcTemplate) {
+        super(jdbcTemplate);
+    }
+
+    @Override
+    public List<Order> findPage(int page, int size, Long customerId, Long productId) {
+        List<Object> args = new ArrayList<>();
+        String where = where(customerId, productId, args);
+        args.add(size);
+        args.add((long) page * size);
+        return getJdbcTemplate().query(SELECT + where + " ORDER BY id LIMIT ? OFFSET ?", rowMapper, args.toArray());
+    }
+
+    @Override
+    public long count(Long customerId, Long productId) {
+        List<Object> args = new ArrayList<>();
+        String where = where(customerId, productId, args);
+        Long total = getJdbcTemplate().queryForObject("SELECT COUNT(*) FROM orders" + where, Long.class, args.toArray());
+        return total == null ? 0L : total;
+    }
+
+    @Override
+    public Optional<Order> findById(Long id) {
+        return findOne(SELECT + " WHERE id = ?", rowMapper, id);
+    }
+
+    @Override
+    public Order insert(Order order) {
+        long id = insertReturningId(
+                "INSERT INTO orders (customer_id, product_id, quantity, total) VALUES (?, ?, ?, ?) RETURNING id",
+                order.getCustomerId(), order.getProductId(), order.getQuantity(), order.getTotal());
+        order.setId(id);
+        return order;
+    }
+
+    /**
+     * Builds the WHERE clause from the non-null filters. Only fixed column names are concatenated,
+     * the values are always bound as parameters and appended to args in placeholder order.
+     */
+    private static String where(Long customerId, Long productId, List<Object> args) {
+        StringBuilder where = new StringBuilder();
+        if (customerId != null) {
+            where.append(" WHERE customer_id = ?");
+            args.add(customerId);
+        }
+        if (productId != null) {
+            where.append(customerId == null ? " WHERE" : " AND").append(" product_id = ?");
+            args.add(productId);
+        }
+        return where.toString();
+    }
+}

core/order/src/main/java/com/edgareldy/springjdbctutorial/core/order/dto/OrderDto.java

@@ -0,0 +1,105 @@
+package com.edgareldy.springjdbctutorial.core.order.dto;
+
+import java.math.BigDecimal;
+import java.util.Objects;
+
+/**
+ * Business shape of an order. The total is computed by the service, never taken from the caller.
+ * <p>
+ * Created edgar.muhamyangabo on 9/20/26
+ * Author : edgar.muhamyangabo
+ * Date : 9/20/26
+ * Project : spring-jdbc-tutorial
+ */
+public class OrderDto {
+
+    private Long id;
+
+    private Long customerId;
+
+    private Long productId;
+
+    private int quantity;
+
+    private BigDecimal total;
+
+    public OrderDto() {
+    }
+
+    public OrderDto(Long id, Long customerId, Long productId, int quantity, BigDecimal total) {
+        this.id = id;
+        this.customerId = customerId;
+        this.productId = productId;
+        this.quantity = quantity;
+        this.total = total;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public Long getCustomerId() {
+        return customerId;
+    }
+
+    public void setCustomerId(Long customerId) {
+        this.customerId = customerId;
+    }
+
+    public Long getProductId() {
+        return productId;
+    }
+
+    public void setProductId(Long productId) {
+        this.productId = productId;
+    }
+
+    public int getQuantity() {
+        return quantity;
+    }
+
+    public void setQuantity(int quantity) {
+        this.quantity = quantity;
+    }
+
+    public BigDecimal getTotal() {
+        return total;
+    }
+
+    public void setTotal(BigDecimal total) {
+        this.total = total;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        OrderDto that = (OrderDto) o;
+        return quantity == that.quantity && Objects.equals(id, that.id) && Objects.equals(customerId, that.customerId)
+                && Objects.equals(productId, that.productId) && Objects.equals(total, that.total);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(id, customerId, productId, quantity, total);
+    }
+
+    @Override
+    public String toString() {
+        return "OrderDto{" +
+                "id=" + id +
+                ", customerId=" + customerId +
+                ", productId=" + productId +
+                ", quantity=" + quantity +
+                ", total=" + total +
+                "}";
+    }
+}