Spring HATEOAS support

spring-security-rest/pom.xml

@@ -76,6 +76,14 @@
             <artifactId>spring-webmvc</artifactId>
             <version>${org.springframework.version}</version>
         </dependency>
+        
+        <!-- Spring HATEOAS -->
+        
+		<dependency>
+		    <groupId>org.springframework.hateoas</groupId>
+		    <artifactId>spring-hateoas</artifactId>
+		    <version>0.19.0.RELEASE</version>
+		</dependency>
 
         <!-- web -->
 

spring-security-rest/src/main/java/org/baeldung/persistence/model/Customer.java

@@ -0,0 +1,56 @@
+package org.baeldung.persistence.model;
+
+import java.util.Map;
+
+import org.springframework.hateoas.ResourceSupport;
+
+public class Customer extends ResourceSupport {
+    private String customerId;
+    private String customerName;
+    private String companyName;
+    private Map<String, Order> orders;
+
+    public Customer() {
+        super();
+    }
+
+    public Customer(final String customerId, final String customerName, final String companyName) {
+        super();
+        this.customerId = customerId;
+        this.customerName = customerName;
+        this.companyName = companyName;
+    }
+
+    public String getCustomerId() {
+        return customerId;
+    }
+
+    public void setCustomerId(final String customerId) {
+        this.customerId = customerId;
+    }
+
+    public String getCustomerName() {
+        return customerName;
+    }
+
+    public void setCustomerName(final String customerName) {
+        this.customerName = customerName;
+    }
+
+    public String getCompanyName() {
+        return companyName;
+    }
+
+    public void setCompanyName(final String companyName) {
+        this.companyName = companyName;
+    }
+
+    public Map<String, Order> getOrders() {
+        return orders;
+    }
+
+    public void setOrders(final Map<String, Order> orders) {
+        this.orders = orders;
+    }
+
+}

spring-security-rest/src/main/java/org/baeldung/persistence/model/Order.java

@@ -0,0 +1,50 @@
+package org.baeldung.persistence.model;
+
+import org.springframework.hateoas.ResourceSupport;
+
+public class Order extends ResourceSupport {
+    private String orderId;
+    private double price;
+    private int quantity;
+
+    public Order() {
+        super();
+    }
+
+    public Order(final String orderId, final double price, final int quantity) {
+        super();
+        this.orderId = orderId;
+        this.price = price;
+        this.quantity = quantity;
+    }
+
+    public String getOrderId() {
+        return orderId;
+    }
+
+    public void setOrderId(final String orderId) {
+        this.orderId = orderId;
+    }
+
+    public double getPrice() {
+        return price;
+    }
+
+    public void setPrice(final double price) {
+        this.price = price;
+    }
+
+    public int getQuantity() {
+        return quantity;
+    }
+
+    public void setQuantity(final int quantity) {
+        this.quantity = quantity;
+    }
+
+    @Override
+    public String toString() {
+        return "Order [orderId=" + orderId + ", price=" + price + ", quantity=" + quantity + "]";
+    }
+
+}

spring-security-rest/src/main/java/org/baeldung/web/controller/CustomerController.java

@@ -0,0 +1,53 @@
+package org.baeldung.web.controller;
+
+import java.util.List;
+
+import org.baeldung.persistence.model.Customer;
+import org.baeldung.persistence.model.Order;
+import org.baeldung.web.service.CustomerService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.hateoas.Link;
+import org.springframework.hateoas.mvc.ControllerLinkBuilder;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class CustomerController {
+    @Autowired
+    private CustomerService customerService;
+
+    @RequestMapping(value = "/customer/{customerId}", method = RequestMethod.GET)
+    public Customer getCustomerById(@PathVariable final String customerId) {
+        return customerService.getCustomerDetail(customerId);
+    }
+
+    @RequestMapping(value = "/customer/{customerId}/{orderId}", method = RequestMethod.GET)
+    public Order getOrderByIdForCustomer(@PathVariable final String customerId, @PathVariable final String orderId) {
+        return customerService.getOrderByIdForCustomer(customerId, orderId);
+    }
+
+    @RequestMapping(value = "/customer/{customerId}/orders", method = RequestMethod.GET)
+    public List<Order> getOrdersForCustomer(@PathVariable final String customerId) {
+        return customerService.getAllOrdersForCustomer(customerId);
+    }
+
+    @RequestMapping(value = "/customers", method = RequestMethod.GET)
+    public List<Customer> getAllCustomers() {
+        final List<Customer> allCustomers = customerService.allCustomers();
+        for (final Customer customer : allCustomers) {
+            final Link selfLink = ControllerLinkBuilder.linkTo(ControllerLinkBuilder.methodOn(CustomerController.class).getCustomerById(customer.getCustomerId())).withSelfRel();
+            customer.add(selfLink);
+            final Link ordersLink = ControllerLinkBuilder.linkTo(ControllerLinkBuilder.methodOn(CustomerController.class).getOrdersForCustomer(customer.getCustomerId())).withRel("allOrders");
+            customer.add(ordersLink);
+
+            for (final Order order : customer.getOrders().values()) {
+                final Link orderLink = ControllerLinkBuilder.linkTo(ControllerLinkBuilder.methodOn(CustomerController.class).getOrderByIdForCustomer(customer.getCustomerId(), order.getOrderId())).withRel("order");
+                order.add(orderLink);
+            }
+        }
+        return allCustomers;
+    }
+
+}

spring-security-rest/src/main/java/org/baeldung/web/service/CustomerService.java

@@ -0,0 +1,18 @@
+package org.baeldung.web.service;
+
+import java.util.List;
+
+import org.baeldung.persistence.model.Customer;
+import org.baeldung.persistence.model.Order;
+
+public interface CustomerService {
+
+    List<Customer> allCustomers();
+
+    Customer getCustomerDetail(final String id);
+
+    List<Order> getAllOrdersForCustomer(String customerId);
+
+    Order getOrderByIdForCustomer(String customerId, String orderId);
+
+}

spring-security-rest/src/main/java/org/baeldung/web/service/CustomerServiceImpl.java

@@ -0,0 +1,69 @@
+package org.baeldung.web.service;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+
+import org.baeldung.persistence.model.Customer;
+import org.baeldung.persistence.model.Order;
+import org.springframework.stereotype.Service;
+
+@Service
+public class CustomerServiceImpl implements CustomerService {
+
+    private HashMap<String, Customer> customerMap;
+    private HashMap<String, Order> customerOneOrderMap;
+    private HashMap<String, Order> customerTwoOrderMap;
+
+    public CustomerServiceImpl() {
+
+        customerMap = new HashMap<>();
+        customerOneOrderMap = new HashMap<>();
+        customerTwoOrderMap = new HashMap<>();
+
+        final Customer customerOne = new Customer("10A", "Jane", "ABC Company");
+        final Customer customerTwo = new Customer("20B", "Bob", "XYZ Company");
+
+        customerOneOrderMap.put("001A", new Order("001A", 150.00, 25));
+        customerOneOrderMap.put("002A", new Order("002A", 250.00, 15));
+
+        customerTwoOrderMap.put("002B", new Order("002B", 550.00, 325));
+        customerTwoOrderMap.put("002B", new Order("002B", 450.00, 525));
+
+        customerOne.setOrders(customerOneOrderMap);
+        customerTwo.setOrders(customerTwoOrderMap);
+        customerMap.put("10A", customerOne);
+        customerMap.put("20B", customerTwo);
+
+    }
+
+    @Override
+    public List<Customer> allCustomers() {
+        return new ArrayList<>(customerMap.values());
+    }
+
+    @Override
+    public Customer getCustomerDetail(final String customerId) {
+        return customerMap.get(customerId);
+    }
+
+    @Override
+    public List<Order> getAllOrdersForCustomer(final String customerId) {
+        return new ArrayList<>(customerMap.get(customerId).getOrders().values());
+    }
+
+    @Override
+    public Order getOrderByIdForCustomer(final String customerId, final String orderId) {
+
+        final List<Order> orders = (List<Order>) customerMap.get(customerId).getOrders().values();
+        Order selectedOrder = null;
+        for (final Order order : orders) {
+            if (order.getId().equals(orderId)) {
+                selectedOrder = order;
+            }
+        }
+        return selectedOrder;
+
+    }
+
+}