Doing a project with parcel service. I created OrderItem API and Dispatcher API. Now, I want to connect then by relations. The idea is: dispatcher can have many orderItems. OrderItem can only have one dispatcher. If you delete dispatcher, his order items also has to go out. I have already created a little bit, but I'm so messed up here and can't finish this thing logically. Would someone give me some ideas on how I should attack this problem.
Do I need to put relations both sides or only to one of them?
When do I need to create constructors with arguments? Because in entity class you have to have no arg constructors...?
OrderItem class:
@Entity
public class OrderItem {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
@NotBlank(message = "Order weight is required")
private String weight;
@NotBlank(message = "Order dimensions are required")
private String dimensions;
@NotBlank(message = "Order origin is required")
private String origin;
@NotBlank(message = "Order destination is required")
private String destination;
@NotNull(message = "Order comment cannot be null")
private String comment;
@ManyToOne
private Dispatcher dispatcher;
public OrderItem() {
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getWeight() {
return weight;
}
public void setWeight(String weight) {
this.weight = weight;
}
public String getDimensions() {
return dimensions;
}
public void setDimensions(String dimensions) {
this.dimensions = dimensions;
}
public String getOrigin() {
return origin;
}
public void setOrigin(String origin) {
this.origin = origin;
}
public String getDestination() {
return destination;
}
public void setDestination(String destination) {
this.destination = destination;
}
public String getComment() {
return comment;
}
public void setComment(String comment) {
this.comment = comment;
}
public Dispatcher getDispatcher() {
return dispatcher;
}
public void setDispatcher(Dispatcher dispatcher) {
this.dispatcher = dispatcher;
}
}
OrderController class:
@RestController
@RequestMapping("/order")
public class OrderController {
@Autowired
OrderService service;
@Autowired
private MapValidationErrorService mapValidationErrorService;
@GetMapping("/{dispatcherId}/orders")
public List<OrderItem> getAllOrderItems(@PathVariable int dispatcherId) {
return service.getAllOrderItems(dispatcherId);
}
@PostMapping("/{dispatcherId}/orders")
public ResponseEntity<?> saveOrder(@Valid @RequestBody OrderItem orderItem, @PathVariable int dispatcherId, BindingResult result) {
ResponseEntity<?> errorMap = mapValidationErrorService.MapValidationService(result);
if (errorMap != null) {
return errorMap;
}
orderItem.setDispatcher(new Dispatcher(dispatcherId, "", "", ""));
service.insertOrUpdate(orderItem);
return new ResponseEntity<String>("Order was created successfully", HttpStatus.CREATED);
}
@PutMapping("/update")
public ResponseEntity<?> updateOrder(@Valid @RequestBody OrderItem orderItem, BindingResult result) {
ResponseEntity<?> errorMap = mapValidationErrorService.MapValidationService(result);
if (errorMap != null) {
return errorMap;
}
service.insertOrUpdate(orderItem);
return new ResponseEntity<String>("Order was updated successfully", HttpStatus.OK);
}
@GetMapping("/all")
public Iterable<OrderItem> getAllOrders() {
return service.findAllOrders();
}
@DeleteMapping("/{orderId}")
public ResponseEntity<String> deleteOrder(@PathVariable int orderId) {
if (service.findById(orderId) == null) {
throw new CustomErrorException("Order doesn't exist, check order id");
}
service.deleteOrder(orderId);
return new ResponseEntity<String>("Order with ID " + orderId + " was deleted", HttpStatus.OK);
}
@GetMapping("/{orderId}")
public ResponseEntity<OrderItem> getOrderById(@PathVariable int orderId) {
OrderItem item = service.findById(orderId);
if (service.findById(orderId) == null) {
throw new CustomErrorException("Order id not found - " + orderId);
}
return new ResponseEntity<OrderItem>(item, HttpStatus.OK);
}
}
Dispatcher class:
@Entity
public class Dispatcher {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
@NotBlank(message = "Dispatcher first name is required")
private String firstName;
@NotBlank(message = "Dispatcher last name is required")
private String lastName;
@NotBlank(message = "Dispatcher email name is required")
private String email;
@NotBlank(message = "Dispatcher email is required")
private String password;
@NotBlank(message = "Dispatcher phone number is required")
private String phoneNumber;
public Dispatcher() {
}
public Dispatcher(int id, String firstName, String lastName, String email) {
super();
this.id = id;
this.firstName = firstName;
this.lastName = lastName;
this.email = email;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getPhoneNumber() {
return phoneNumber;
}
public void setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
}
}
DispatcherController class:
@RestController
@RequestMapping("/dispatcher")
public class DispatcherController {
@Autowired
DispatcherService service;
@Autowired
private MapValidationErrorService mapValidationErrorService;
@PostMapping("/save")
public ResponseEntity<?> saveDispatcher(@Valid @RequestBody Dispatcher dispatcher, BindingResult result) {
ResponseEntity<?> errorMap = mapValidationErrorService.MapValidationService(result);
if (errorMap != null) {
return errorMap;
}
service.insertOrUpdate(dispatcher);
return new ResponseEntity<String>("Dispatcher was created successfully", HttpStatus.CREATED);
}
@GetMapping("/all")
public Iterable<Dispatcher> getAllDispatchers() {
return service.findAllDispatchers();
}
@GetMapping("/{dispatcherId}")
public ResponseEntity<?> getDispatcherById(@PathVariable int dispatcherId) {
Dispatcher dispatcher = service.findById(dispatcherId);
if (service.findById(dispatcherId) == null) {
throw new CustomErrorException("Dispatcher id not found - " + dispatcherId);
}
return new ResponseEntity<Dispatcher>(dispatcher, HttpStatus.OK);
}
@DeleteMapping("/{dispatcherId}")
public ResponseEntity<?> deleteDispatcher(@PathVariable int dispatcherId) {
if (service.findById(dispatcherId) == null) {
throw new CustomErrorException("Dispatcher doesn't exist, check dispatcher id");
}
service.deleteDispatcher(dispatcherId);
return new ResponseEntity<String>("Order with ID " + dispatcherId + " was deleted", HttpStatus.OK);
}
@PutMapping("/update")
public ResponseEntity<?> updateDispatcher(@Valid @RequestBody Dispatcher dispatcher, BindingResult result) {
ResponseEntity<?> errorMap = mapValidationErrorService.MapValidationService(result);
if (errorMap != null) {
return errorMap;
}
service.insertOrUpdate(dispatcher);
return new ResponseEntity<String>("Dispatcher was updated successfully", HttpStatus.OK);
}
}
I think you have defined the relationship incorrectly. And yes you need to have no-args constructor. This helps hibernate to map the values from database to java objects when retrieving data from the database
Assuming you are going for a uni-directional mapping,
@Entity
public class OrderItem {
@ManyToOne( cascade = CascadeType.ALL )
@JoinColumn(name = <foriegn_key_column in orderItem table i.e. id>)
private Dispatcher dispatcher;
}
@Entity
public class Dispatcher {
private List<OrderItem > orders;
}