[3단계]- 자동차 경주

README.md

@@ -6,4 +6,19 @@
 * 모든 피드백을 완료하면 다음 단계를 도전하고 앞의 과정을 반복한다.
 
 ## 온라인 코드 리뷰 과정
-* [텍스트와 이미지로 살펴보는 온라인 코드 리뷰 과정](https://github.com/next-step/nextstep-docs/tree/master/codereview)
+* [텍스트와 이미지로 살펴보는 온라인 코드 리뷰 과정](https://github.com/next-step/nextstep-docs/tree/master/codereview)
+
+### 제약사항
+- [x] 모든 로직에 단위 테스트를 구현한다.
+    - UI 로직은 제외한다
+    - UI 로직은 클래스를 분리한다. 
+- [x] else 예약어는 쓰지 않는다.
+
+### 요구사항
+- [x] 주어진 횟수 동안 n대의 자동차는 전진 또는 멈출 수 있다.
+- [x] 몇대의 자동차로 몇 번의 이동을 할 것인지 입력할 수 있다.
+  - 입력받는 API는 Scanner를 이용한다. 
+- [x] 0 ~ 9 사이의 random 값 중 4 이상일 때 전진한다.
+  - 랜덤값은 Random 클래스 이용한다.
+- [x] 자동차의 상태를 콘솔에 출력한다.
+

src/main/java/racing/RacingGameApplication.java

@@ -0,0 +1,27 @@
+package racing;
+
+import static racing.view.InputView.getCarCount;
+import static racing.view.InputView.getMoveCount;
+
+import racing.model.Cars;
+import racing.service.RaceService;
+import racing.service.RandomNumberGenerator;
+import racing.view.OutputView;
+
+public class RacingGameApplication {
+    private static final int RAND = 10;
+
+    public static void main(String[] args) {
+        int carCount = getCarCount();
+        int moveCount = getMoveCount();
+
+        RaceService raceService = new RaceService(new RandomNumberGenerator(RAND));
+        Cars cars = raceService.generateCar(carCount);
+
+        OutputView.printResultLabel();
+        for (int i = 0; i < moveCount; i++) {
+            raceService.moveCar(cars);
+            OutputView.printResult(cars);
+        }
+    }
+}

src/main/java/racing/model/Car.java

@@ -0,0 +1,20 @@
+package racing.model;
+
+public class Car {
+    private static final int MOVE_CONDITION = 4;
+    private int position;
+
+    public Car() {
+        this.position = 0;
+    }
+
+    public void move(int number) {
+        if (number >= MOVE_CONDITION) {
+            this.position++;
+        }
+    }
+
+    public int getPosition() {
+        return position;
+    }
+}

src/main/java/racing/model/Cars.java

@@ -0,0 +1,34 @@
+package racing.model;
+
+import java.util.ArrayList;
+import java.util.List;
+import racing.service.NumberGenerator;
+
+public class Cars {
+    private final List<Car> cars;
+    private final NumberGenerator numberGenerator;
+
+    public Cars(List<Car> cars, NumberGenerator numberGenerator) {
+        this.cars = cars;
+        this.numberGenerator = numberGenerator;
+    }
+
+    public void moveAll() {
+        for (Car car : cars) {
+            car.move(numberGenerator.generateNumber());
+        }
+    }
+
+    public List<Integer> getPositions() {
+        List<Integer> positions = new ArrayList<>();
+        for (Car car : cars) {
+            positions.add(car.getPosition());
+        }
+        return positions;
+    }
+
+    public int size() {
+        return cars.size();
+    }
+
+}

src/main/java/racing/service/NumberGenerator.java

@@ -0,0 +1,5 @@
+package racing.service;
+
+public interface NumberGenerator {
+    int generateNumber();
+}

src/main/java/racing/service/RaceService.java

@@ -0,0 +1,30 @@
+package racing.service;
+
+import java.util.ArrayList;
+import java.util.List;
+import racing.model.Car;
+import racing.model.Cars;
+
+public class RaceService {
+    private final NumberGenerator numberGenerator;
+
+    public RaceService(NumberGenerator numberGenerator) {
+        this.numberGenerator = numberGenerator;
+    }
+
+    public Cars generateCar(int carCount) {
+        List<Car> carList = new ArrayList<>();
+
+        for (int i = 0; i < carCount; i++) {
+            Car car = new Car();
+            carList.add(car);
+        }
+
+        return new Cars(carList, numberGenerator);
+    }
+
+    public void moveCar(Cars cars) {
+        cars.moveAll();
+    }
+
+}

src/main/java/racing/service/RandomNumberGenerator.java

@@ -0,0 +1,16 @@
+package racing.service;
+
+import java.util.Random;
+
+public class RandomNumberGenerator implements NumberGenerator {
+    private final int rand;
+
+    public RandomNumberGenerator(int rand) {
+        this.rand = rand;
+    }
+
+    @Override
+    public int generateNumber() {
+        return new Random().nextInt(rand);
+    }
+}

src/main/java/racing/view/InputView.java

@@ -0,0 +1,18 @@
+package racing.view;
+
+import java.util.Scanner;
+
+public class InputView {
+    private static final Scanner scanner = new Scanner(System.in);
+
+    public static int getCarCount() {
+        System.out.println("자동차 대수는 몇 대 인가요?");
+        return scanner.nextInt();
+    }
+
+    public static int getMoveCount() {
+        System.out.println("시도할 횟수는 몇 대 인가요?");
+        return scanner.nextInt();
+    }
+
+}

src/main/java/racing/view/OutputView.java

@@ -0,0 +1,22 @@
+package racing.view;
+
+import java.util.List;
+import racing.model.Cars;
+
+public class OutputView {
+
+    public static final String RESULT_LABEL = "실행 결과";
+
+    public static void printResultLabel() {
+        System.out.println(RESULT_LABEL);
+    }
+
+    public static void printResult(Cars cars) {
+        List<Integer> positions = cars.getPositions();
+        for (Integer position : positions) {
+            System.out.println("-".repeat(position));
+        }
+        System.out.println();
+    }
+
+}

src/test/java/racing/fake/FakeNumberGenerator.java

@@ -0,0 +1,16 @@
+package racing.fake;
+
+import racing.service.NumberGenerator;
+
+public class FakeNumberGenerator implements NumberGenerator {
+    private final int num;
+
+    public FakeNumberGenerator(int num) {
+        this.num = num;
+    }
+
+    @Override
+    public int generateNumber() {
+        return num;
+    }
+}

src/test/java/racing/model/CarTest.java

@@ -0,0 +1,38 @@
+package racing.model;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+class CarTest {
+    private Car car;
+
+    @BeforeEach
+    void setUp() {
+        this.car = new Car();
+    }
+
+    @DisplayName("자동차의 위치를 한 칸 증가시킬 수 있다.")
+    @ParameterizedTest
+    @ValueSource(ints = {4, 9})
+    void carMoveTest(int argument) {
+        car.move(argument);
+
+        assertThat(car.getPosition()).isEqualTo(1);
+    }
+
+    @DisplayName("파라미터로 받는 숫자가 4 미만인 경우 자동차는 멈춘다.")
+    @ParameterizedTest
+    @ValueSource(ints = {0, 3})
+    void carNotMoveTest(int argument) {
+        car.move(argument);
+
+        assertThat(car.getPosition()).isEqualTo(0);
+    }
+
+}

src/test/java/racing/model/CarsTest.java

@@ -0,0 +1,64 @@
+package racing.model;
+
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import racing.fake.FakeNumberGenerator;
+
+class CarsTest {
+    private static final int MOVE_NUMBER = 4;
+    private static final int STOP_NUMBER = 3;
+    private Cars cars;
+
+    @DisplayName("리스트 안의 모든 자동차를 움직일 수 있다.")
+    @Test
+    void moveAllTest() {
+        // given
+        cars = new Cars(makeDummyCars(3), new FakeNumberGenerator(MOVE_NUMBER));
+
+        // when
+        cars.moveAll();
+
+        // then
+        assertThat(cars.getPositions()).isEqualTo(Arrays.asList(1, 1, 1));
+    }
+
+    @DisplayName("리스트 안의 모든 자동차들의 현재 위치를 알 수 있다.")
+    @Test
+    void getPositionsTest() {
+        // given
+        cars = new Cars(makeDummyCars(7), new FakeNumberGenerator(STOP_NUMBER));
+
+        // when
+        List<Integer> positions = cars.getPositions();
+
+        // then
+        Assertions.assertAll(() -> assertThat(positions).isNotNull(),
+                () -> assertThat(positions).containsExactly(0, 0, 0, 0, 0, 0, 0));
+    }
+
+    @DisplayName("일급 콜렉션 안의 리스트의 총 개수를 알 수 있다.")
+    @Test
+    void sizeTest() {
+        // given
+        cars = new Cars(makeDummyCars(5), new FakeNumberGenerator(MOVE_NUMBER));
+
+        // when
+        // then
+        assertThat(cars.size()).isEqualTo(5);
+    }
+
+    private List<Car> makeDummyCars(int carCount) {
+        List<Car> carList = new ArrayList<>();
+        for (int i = 0; i < carCount; i++) {
+            carList.add(new Car());
+        }
+        return carList;
+    }
+}

src/test/java/racing/service/RaceServiceTest.java

@@ -0,0 +1,45 @@
+package racing.service;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.Arrays;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import racing.fake.FakeNumberGenerator;
+import racing.model.Cars;
+
+class RaceServiceTest {
+    private RaceService raceService;
+
+    @BeforeEach
+    void setUp() {
+        raceService = new RaceService(new FakeNumberGenerator(4));
+    }
+
+    @DisplayName("입력 받은 n대의 자동차를 생성한다.")
+    @Test
+    void generateCarsTest() {
+        // given
+        int carCount = 3;
+
+        // when
+        Cars cars = raceService.generateCar(carCount);
+
+        // then
+        assertThat(cars.size()).isEqualTo(carCount);
+    }
+
+    @DisplayName("자동차를 움직일 수 있다.")
+    @Test
+    void moveCarTest() {
+        // given
+        Cars cars = raceService.generateCar(3);
+
+        // when
+        raceService.moveCar(cars);
+
+        // then
+        assertThat(cars.getPositions()).isEqualTo(Arrays.asList(1, 1, 1));
+    }
+}