[그리디]김태우 자동차 경주 미션 3,4단계 제출합니다.

README.md

@@ -3,10 +3,11 @@
 ## 클래스 구성
 
 - **Car** → 자동차 1대 관리 (이름, 위치, 이동 로직)
-- **Cars** → 자동차 리스트 관리 (생성, 조회)
+- **CarName** ->
+- **Cars** → 자동차 이름을 표현·검증하는 값 객체(공백·길이 제한 등 유효성 검사 담당)
 - **GameManage** → 경주 전체 진행 (라운드별 이동, 결과 출력, 우승자 계산)
 - **Winners** → 우승자 저장소
-- **Generater** → 랜덤 숫자 생성 (0~9)
+- **GenerateNumber** → 랜덤 숫자 생성 (0~9)
 - **InputView** → 사용자 입력 (자동차 이름, 시도 횟수)
 - **ResultView** → 결과 출력 (라운드별, 최종 우승자)
 - **Main** → 게임 실행 흐름

src/main/java/Main.java

@@ -4,21 +4,17 @@
 import view.InputView;
 import view.ResultView;
 
-import java.util.List;
 
 public class Main {
     public static void main(String[] args) {
-
-        List<String> carNames = InputView.inputCarName();
+        Cars cars = InputView.inputCarName();
         int roundCount = InputView.inputRound();
-
-        Cars cars = Cars.carsCreate(carNames);
-        Winners winners = Winners.winnersCreate();
-
-        GameManage game = new GameManage(cars, winners);
-
-        game.race(roundCount);
-        ResultView.printWinners(game.getWinners().getWinners());
-
+        GameManage game = new GameManage(cars);
+        for (int i = 0; i < roundCount; i++) {
+            game.raceOneRound();
+            ResultView.printRoundResult(cars.getCars());
+        }
+        Winners winners = game.createWinners();
+        ResultView.printWinners(winners.getWinners());
     }
 }

src/main/java/domain/Car.java

@@ -1,32 +1,31 @@
 package domain;
 
-import util.Generater;
-
+import util.GenerateNumber;
 
 public class Car {
     private static final int STANDARD = 4;
 
-    private final String carName;
+    private final CarName carName;
     private int carPosition;
 
-    private Car(String carName) {
+    private Car(CarName carName) {
         this.carName = carName;
         this.carPosition = 0;
     }
 
-    public static Car namePositionOf(String carName) {
+    public static Car createCarByCarName(CarName carName) {
         return new Car(carName);
     }
 
-    public void move() {
-        int randomNumber = Generater.generateNumber();
+    public void moveCar() {
+        int randomNumber = GenerateNumber.generateNumber();
         if (randomNumber >= STANDARD) {
             carPosition++;
         }
     }
 
     public String getCarName() {
-        return carName;
+        return carName.getCarName();
     }
 
     public int getCarPosition() {

src/main/java/domain/CarName.java

@@ -0,0 +1,27 @@
+package domain;
+
+public class CarName {
+    private final String carName;
+
+    public CarName(String carName) {
+        checkNull(carName);
+        checkLength(carName);
+        this.carName = carName;
+    }
+
+    private static void checkNull(String carName) {
+        if (carName == null || carName.isBlank()) {
+            throw new IllegalArgumentException("이름은 공백으로 입력될 수 없습니다.");
+        }
+    }
+
+    private static void checkLength(String carName) {
+        if (carName.length() > 5) {
+            throw new IllegalArgumentException("자동차 이름은 최대 5글자까지만 가능합니다. 입력값:" + carName);
+        }
+    }
+
+    public String getCarName() {
+        return carName;
+    }
+}

src/main/java/domain/Cars.java

@@ -1,19 +1,28 @@
 package domain;
 
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 public class Cars {
-    private List<Car> cars;
+    private final List<Car> cars;
 
     private Cars() {
         this.cars = new ArrayList<>();
     }
 
-    public static Cars carsCreate(List<String> carNames) {
+    public static Cars createCars(List<String> carNames) {
         Cars cars = new Cars();
+        Set<String> existingNames = new HashSet<>();
         for (String name : carNames) {
-            cars.addCar(Car.namePositionOf(name));
+            String trimmed = name.trim();
+            if (existingNames.contains(trimmed)) {
+                throw new IllegalArgumentException("중복된 자동차 이름이 있습니다: " + name);
+            }
+            existingNames.add(trimmed);
+            CarName nameObj = new CarName(trimmed);
+            cars.addCar(Car.createCarByCarName(nameObj));
         }
         return cars;
     }
@@ -23,6 +32,6 @@ public void addCar(Car car) {
     }
 
     public List<Car> getCars() {
-        return cars;
+        return List.copyOf(cars);
     }
 }

src/main/java/domain/GameManage.java

@@ -1,47 +1,39 @@
 package domain;
 
-import view.ResultView;
-
+import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import java.util.stream.Collectors;
 
 public class GameManage {
     private final Cars cars;
-    private final Winners winners;
 
-    public GameManage(Cars cars, Winners winners) {
+    public GameManage(Cars cars) {
         this.cars = cars;
-        this.winners = winners;
     }
 
     public void raceOneRound() {
         for (Car car : cars.getCars()) {
-            car.move();
+            car.moveCar();
         }
     }
 
-    public void race(int round) {
-        for (int i = 0; i < round; i++) {
-            raceOneRound();
-            ResultView.printRoundResult(cars.getCars());
-        }
-        findWinner();
+    private Map<Integer, List<Car>> groupPosition() {
+        return cars.getCars().stream().collect(Collectors.groupingBy(Car::getCarPosition));
     }
 
-    private int maxPosition() {
-        return cars.getCars().stream().mapToInt(Car::getCarPosition).max().orElse(0);
-    }
+    public Winners createWinners() {
+        Map<Integer, List<Car>> carsByPosition = groupPosition();
 
-    public void findWinner() {
-        List<String> winnerNames = cars.getCars().stream()
-                .filter(car -> car.getCarPosition() == maxPosition())
+        List<Car> winnersGroup = carsByPosition.entrySet().stream()
+                .max(Map.Entry.comparingByKey())
+                .map(Map.Entry::getValue)
+                .orElse(Collections.emptyList());
+
+        List<String> winnerNames = winnersGroup.stream()
                 .map(Car::getCarName)
                 .collect(Collectors.toList());
 
-        winners.setWinners(winnerNames);
-    }
-
-    public Winners getWinners() {
-        return winners;
+        return Winners.of(winnerNames);
     }
 }

src/main/java/domain/Winners.java

@@ -6,21 +6,14 @@
 public class Winners {
     private List<String> winners;
 
-    private Winners() {
-        this.winners = new ArrayList<>();
+    private Winners(List<String> winners) {
+        this.winners = List.copyOf(winners);
     }
 
-    public static Winners winnersCreate() {
-        return new Winners();
+    public static Winners of(List<String> winnerNames) {
+        return new Winners(winnerNames);
     }
 
-
-    public void setWinners(List<String> winnerNames) {
-        this.winners.clear();
-        this.winners.addAll(winnerNames);
-    }
-
-
     public List<String> getWinners() {
         return winners;
     }

src/main/java/util/GenerateNumber.java

@@ -0,0 +1,11 @@
+package util;
+
+import java.util.Random;
+
+public class GenerateNumber {
+    private static final Random random = new Random();
+
+    public static int generateNumber() {
+        return random.nextInt(10);
+    }
+}

src/main/java/view/InputView.java

@@ -1,20 +1,44 @@
 package view;
 
+import domain.Cars;
+
 import java.util.Arrays;
+import java.util.InputMismatchException;
 import java.util.List;
 import java.util.Scanner;
 
 public class InputView {
     private static final Scanner scanner = new Scanner(System.in);
 
-    public static List<String> inputCarName() {
-        System.out.println("경주할 자동차 이름을 입력하세요(이름은 쉼표(,)를 기준으로 구분).");
-        String inputName = scanner.nextLine();
-        return Arrays.asList(inputName.split(","));
+    public static Cars inputCarName() {
+        while (true) {
+            try {
+                System.out.println("경주할 자동차 이름을 입력하세요(이름은 쉼표(,)를 기준으로 구분).");
+                String[] inputName = scanner.nextLine().split(",");
+                for (int i = 0; i < inputName.length; i++) {
+                    inputName[i] = inputName[i].trim();
+                }
+                List<String> names = Arrays.asList(inputName);
+
+                return Cars.createCars(names);
+
+            } catch (IllegalArgumentException input) {
+                System.out.println("입력 오류이므로 다시 입력해주세요.");
+            }
+        }
     }
 
     public static int inputRound() {
         System.out.println("시도할 회수는 몇회인가요?");
-        return scanner.nextInt();
+        while (true) {
+            try {
+                int round = scanner.nextInt();
+                scanner.nextLine();
+                return round;
+            } catch (InputMismatchException input) {
+                System.out.println("회수는 숫자로 입력해 주세요!!");
+                scanner.nextLine();
+            }
+        }
     }
 }

src/test/java/domain/CarNameTest.java

@@ -0,0 +1,25 @@
+package domain;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class CarNameTest {
+
+    @Test
+    void 정상적인_이름이면_생성된다() {
+        CarName carName = new CarName("car1");
+        assertEquals("car1", carName.getCarName());
+    }
+
+    @Test
+    void null이나공백이면_예외가_발생한다() {
+        assertThrows(IllegalArgumentException.class, () -> new CarName(null));
+        assertThrows(IllegalArgumentException.class, () -> new CarName("   "));
+    }
+
+    @Test
+    void 다섯글자를_초과하면_예외가_발생한다() {
+        assertThrows(IllegalArgumentException.class, () -> new CarName("aaaaaa"));
+    }
+}

src/test/java/domain/CarTest.java

@@ -2,34 +2,38 @@
 
 import org.junit.jupiter.api.Test;
 
-import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+import java.util.Arrays;
+import java.util.List;
 
-class CarTest {
+import static org.junit.jupiter.api.Assertions.*;
 
+class CarsTest {
     @Test
-    void 자동차는이름과초기위치를가진다() {
+    void 이름리스트로Cars를생성한다() {
         // given
-        String name = "car1";
+        List<String> carNames = Arrays.asList("car1", "car2", "car3");
 
         // when
-        Car car = Car.namePositionOf(name);
+        Cars cars = Cars.createCars(carNames);
 
         // then
-        assertThat(car.getCarName()).isEqualTo("car1");
-        assertThat(car.getCarPosition()).isZero();
+        assertEquals(3, cars.getCars().size());
+        assertEquals("car1", cars.getCars().get(0).getCarName());
+        assertEquals("car2", cars.getCars().get(1).getCarName());
+        assertEquals("car3", cars.getCars().get(2).getCarName());
     }
 
     @Test
-    void 랜덤숫자가4이상이면전진할수있다() {
+    void 자동차를추가할수있다() {
         // given
-        Car car = Car.namePositionOf("car1");
+        Cars cars = Cars.createCars(Arrays.asList("car1"));
+        Car car2 = Car.createCarByCarName(new CarName("car2"));
 
         // when
-        for (int i = 0; i < 10; i++) {
-            car.move();
-        }
+        cars.addCar(car2);
 
         // then
-        assertThat(car.getCarPosition()).isGreaterThanOrEqualTo(0);
+        assertEquals(2, cars.getCars().size());
+        assertEquals("car2", cars.getCars().get(1).getCarName());
     }
 }