[TEST] Add unit tests. Refactor code. Fix bug with updateCar method, …

…add new method in CarMapper

src/main/java/service/carsharing/mapper/CarMapper.java

@@ -1,6 +1,7 @@
 package service.carsharing.mapper;
 
 import org.mapstruct.Mapper;
+import org.mapstruct.MappingTarget;
 import service.carsharing.config.MapperConfig;
 import service.carsharing.dto.cars.CarRequestDto;
 import service.carsharing.dto.cars.CarResponseDto;
@@ -11,4 +12,6 @@ public interface CarMapper {
     Car toModel(CarRequestDto requestDto);
 
     CarResponseDto toDto(Car car);
+
+    void updateCar(CarRequestDto requestDto, @MappingTarget Car car);
 }

src/main/java/service/carsharing/service/impl/CarServiceImpl.java

@@ -2,7 +2,6 @@
 
 import jakarta.persistence.EntityNotFoundException;
 import java.util.List;
-import java.util.Optional;
 import lombok.RequiredArgsConstructor;
 import org.springframework.data.domain.Pageable;
 import org.springframework.stereotype.Service;
@@ -34,22 +33,23 @@ public List<CarResponseDto> getAllCars(Pageable pageable) {
 
     @Override
     public CarResponseDto getCar(Long id) {
-        Optional<Car> carById = carRepository.findByIdAndDeletedFalse(id);
-        if (carById.isPresent()) {
-            return carMapper.toDto(carById.get());
-        }
-        throw new EntityNotFoundException("Can't find car with id: " + id);
+        return carMapper.toDto(getCarById(id));
     }
 
     @Override
     public CarResponseDto updateCar(Long id, CarRequestDto requestDto) {
-        carRepository.findByIdAndDeletedFalse(id).orElseThrow(
-                () -> new EntityNotFoundException("Can't find car with id: " + id));
-        return carMapper.toDto(carRepository.save(carMapper.toModel(requestDto)));
+        Car car = getCarById(id);
+        carMapper.updateCar(requestDto, car);
+        return carMapper.toDto(carRepository.save(car));
     }
 
     @Override
     public void deleteCar(Long id) {
         carRepository.softDelete(id);
     }
+
+    private Car getCarById(Long id) {
+        return carRepository.findByIdAndDeletedFalse(id).orElseThrow(
+                () -> new EntityNotFoundException("Can't find car with id: " + id));
+    }
 }

src/main/java/service/carsharing/service/impl/RentalServiceImpl.java

@@ -25,6 +25,8 @@
 @RequiredArgsConstructor
 @Service
 public class RentalServiceImpl implements RentalService {
+    private static final Integer MIN_REQUIRED_CAR_AVAILABLE = 1;
+
     private final RentalRepository rentalRepository;
     private final UserRepository userRepository;
     private final CarRepository carRepository;
@@ -39,13 +41,7 @@ public RentalResponseDto addNewRental(RentalRequestDto requestDto) {
             throw new RuntimeException("You have expired payments, denied access");
         }
         Car car = getCarById(requestDto.carId());
-        if (car.getInventory() < 1) {
-            notificationService.sendNotification(requestDto.userId(),
-                    "There is no free available car with id: "
-                            + requestDto.carId());
-            throw new RuntimeException("There is no free available car with id: "
-                    + requestDto.carId());
-        }
+        checkIsExistsAvailableCar(requestDto, car);
         car.setInventory(car.getInventory() - 1);
         carRepository.save(car);
         RentalResponseDto responseDto = rentalMapper.toDto(rentalRepository
@@ -113,6 +109,16 @@ private boolean canBorrow(Long userId) {
         return expiredState.isEmpty();
     }
 
+    private void checkIsExistsAvailableCar(RentalRequestDto requestDto, Car car) {
+        if (car.getInventory() < MIN_REQUIRED_CAR_AVAILABLE) {
+            notificationService.sendNotification(requestDto.userId(),
+                    "There is no free available car with id: "
+                            + requestDto.carId());
+            throw new RuntimeException("There is no free available car with id: "
+                    + requestDto.carId());
+        }
+    }
+
     private String createOverdueRentalMessage(Rental rental) {
         return "Overdue rental alert! Rental ID: " + rental.getId()
                 + ", User ID: " + rental.getUser().getId()

src/main/java/service/carsharing/service/impl/UserServiceImpl.java

@@ -37,11 +37,8 @@ public UserResponseDto registration(UserRegistrationRequestDto requestDto) {
 
     @Override
     public UserWithRoleResponseDto updateRole(Long id, UserUpdateRoleRequestDto requestDto) {
-        User user = userRepository.findByIdAndDeletedFalse(id)
-                .orElseThrow(() -> new EntityNotFoundException("Can't find user with id: " + id));
-        Role.RoleName roleName = Role.RoleName.valueOf(requestDto.role());
-        Role role = roleRepository.findByName(roleName).orElseThrow(
-                        () -> new EntityNotFoundException("Can't find role with name=" + roleName));
+        User user = getUserById(id);
+        Role role = getRoleByRoleName(requestDto.role());
         user.getRoles().add(role);
         return userMapper.toDtoWithRole(userRepository.save(user));
     }
@@ -63,4 +60,15 @@ private User getUserByEmail(String email) {
         return userRepository.findByEmail(email).orElseThrow(
                 () -> new EntityNotFoundException("Can't find user with email: " + email));
     }
+
+    private User getUserById(Long id) {
+        return userRepository.findByIdAndDeletedFalse(id)
+                .orElseThrow(() -> new EntityNotFoundException("Can't find user with id: " + id));
+    }
+
+    private Role getRoleByRoleName(String role) {
+        Role.RoleName roleName = Role.RoleName.valueOf(role);
+        return roleRepository.findByName(roleName).orElseThrow(
+                () -> new EntityNotFoundException("Can't find role with name=" + roleName));
+    }
 }

src/test/java/service/carsharing/CarSharingApplicationTests.java

@@ -1,11 +1,7 @@
 package service.carsharing;
 
-import org.junit.jupiter.api.Test;
 import org.springframework.boot.test.context.SpringBootTest;
 
 @SpringBootTest
 class CarSharingApplicationTests {
-    @Test
-    void contextLoads(){
-    }
 }