[ 자동차 경주 - 초간단 애플리케이션 ] 미션 제출

README.md

@@ -0,0 +1,32 @@
+### 1단계
+- 자동차는 이름을 갖는다.
+- 자동차는 0-9 사이 랜덤 값을 구한 후 4이상이면 전진, 3이하면 멈춘다.
+- 3항 연산자를 쓰지 않는다.
+- else 예약어, switch/case 허용하지 않는다.
+- 메소드 길이가 15라인이 넘어가지 않도록 구현한다
+- 메인 메소드를 만들지 않는다.
+- 테스트 코드 작성한다.
+
+### 2단계
+- n대의 자동차가 참여가능하다.
+- 주어진 횟수동안 자동차 경주 게임을 완료한 후 누가 우승했는지 알 수 있다.
+- 우승자는 한 명 이상일 수 있다.
+- 나머진 1단계와 유사하다.
+
+### 3단계
+- 자동차에 이름 부여가능하고, 전진하는 자동차 출력할 때 자동차 이름을 같이 출력한다.
+- 자동차 이름은 , 기준으로 구분하며 이름은 5자 이하만 가능하다.
+- 메인 메소드를 추가한다.
+
+### 4단계
+- 모든 로직에 단위 테스트를 구현한다.
+- mvc 패턴으로 리팩터링한다.
+
+### 개인적 목표
+1. 주석이 없어도 읽기 좋은 코드를 짜보자.
+2. 메서드가 한가지 기능만 갖도록 분리하다가 따로 관리하는게 좋을 것 같으면 클래스로 구현하자.
+3. 단위 테스트 핵심 원칙을 따르자.
+4. 개념에 머무르고 있었던 객체 지향적 개념을 활용하여 코드를 작성해보자.
+5. 발생할 수 있는 예외 케이스를 고려하여 방어적인 코드를 작성하고, 이를 테스트 코드로 확인하자.
+
+

build.gradle

@@ -14,6 +14,7 @@ dependencies {
     testImplementation platform('org.assertj:assertj-bom:3.25.1')
     testImplementation('org.junit.jupiter:junit-jupiter')
     testImplementation('org.assertj:assertj-core')
+    developmentOnly('org.springframework.boot:spring-boot-devtools')
 }
 
 test {

src/main/java/racinggame/Main.java

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+package racinggame;
+
+import racinggame.controller.RacingGameController;
+
+public class Main {
+    public static void main(String[] args) {
+        new RacingGameController().run();
+    }
+}

src/main/java/racinggame/controller/RacingGameController.java

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+package racinggame.controller;
+
+import racinggame.model.RacingGame;
+import racinggame.model.car.policy.numbergenerator.ZeroToNineRandomGenerator;
+import racinggame.model.car.policy.decider.ThresholdBaseMoveDecider;
+import racinggame.model.car.policy.evaluator.GreaterThanOrEqualThresholdEvaluator;
+import racinggame.model.car.policy.strategy.MoveStrategy;
+import racinggame.model.car.policy.strategy.OneStepMoveStrategy;
+import racinggame.view.InputView;
+import racinggame.view.OutputView;
+
+import java.util.List;
+
+public class RacingGameController {
+    public void run(){
+        List<String> names= InputView.readCarNames();
+        int moveCount = InputView.readMoveCount();
+
+        MoveStrategy strategy = new OneStepMoveStrategy(
+                new ZeroToNineRandomGenerator(),
+                new ThresholdBaseMoveDecider(new GreaterThanOrEqualThresholdEvaluator(4)));
+
+        RacingGame game = new RacingGame(names,strategy);
+
+        for (int i = 0; i < moveCount; i++) {
+            game.moveOneTurn();
+            OutputView.printResult(game.getCars());
+        }
+
+        List<String> winners = game.getWinners();
+        OutputView.printWinner(winners);
+    }
+}

src/main/java/racinggame/model/RacingGame.java

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+package racinggame.model;
+import racinggame.model.car.Car;
+import racinggame.model.car.policy.strategy.MoveStrategy;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class RacingGame {
+    private final List<Car> cars;
+
+    public RacingGame(List<String> names,MoveStrategy moveStrategy) {
+        this.cars = createCars(names,moveStrategy);
+    }
+
+    private List<Car> createCars(List<String> names, MoveStrategy strategy) {
+        return names.stream()
+                .map(name -> new Car(name,strategy))
+                .collect(Collectors.toList());
+    }
+
+    public void moveOneTurn() {
+        for (Car car : cars) {
+            car.move();
+        }
+    }
+
+    public List<Car> getCars() {
+        return cars;
+    }
+
+    public List<String> getWinners(){
+        int maxDistance=findMaxDistance();
+
+        return cars.stream()
+                .filter(car->car.getMovedDistance()==maxDistance)
+                .map(Car::getName).collect(Collectors.toList());
+    }
+
+    private int findMaxDistance(){
+        return cars.stream()
+                .mapToInt(Car::getMovedDistance)
+                .max()
+                .orElse(0);
+    }
+}

src/main/java/racinggame/model/WinnerFinder.java

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+package racinggame.model;
+
+import racinggame.model.car.Car;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+public class WinnerFinder {
+    private final List<Car> cars;
+    private final int moveCount;
+    public WinnerFinder(List<Car> cars, int moveCount){
+        this.cars = cars;
+        this.moveCount = moveCount;
+    }
+
+    public void play(){
+        for(int i=0;i<moveCount;i++){
+            moveAllCars();
+        }
+    }
+    public List<String> getWinners(){
+        int maxDistance=maxDistance();
+        return cars.stream().filter(car->car.getMovedDistance()==maxDistance).map(Car::getName).collect(Collectors.toList());
+    }
+
+    private void moveAllCars( ){
+        for (Car car : cars) {
+            car.move();
+        }
+    }
+    private int maxDistance(){
+        int max=0;
+        for (Car car : cars) {
+            max=Math.max(max,car.getMovedDistance());
+        }
+        return max;
+    }
+}

src/main/java/racinggame/model/car/Car.java

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+package racinggame.model.car;
+
+import racinggame.model.car.policy.strategy.MoveStrategy;
+
+import java.util.Objects;
+
+public class Car {
+    private final String name;
+    private int movedDistance=0;
+
+    private final MoveStrategy moveStrategy;
+
+    public Car(String name,MoveStrategy moveStrategy) {
+        if(name==null){
+            throw new IllegalArgumentException("이름은 null 일 수 없습니다.");
+        }
+        if(name.isBlank()){
+            throw new IllegalArgumentException("이름은 공백일 수 없습니다.");
+        }
+        this.name = name;
+        this.moveStrategy=moveStrategy;
+    }
+
+    public void move(){
+        int distance=moveStrategy.addStepSize();
+        movedDistance+=distance;
+    }
+
+    public int getMovedDistance() {
+        return movedDistance;
+    }
+    public String getName() {
+        return name;
+    }
+}

src/main/java/racinggame/model/car/policy/decider/MoveDecider.java

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+package racinggame.model.car.policy.decider;
+
+public interface MoveDecider {
+    boolean canMove(int randomNumber);
+}

src/main/java/racinggame/model/car/policy/decider/ThresholdBaseMoveDecider.java

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+package racinggame.model.car.policy.decider;
+
+import racinggame.model.car.policy.evaluator.ThresholdEvaluator;
+
+public class ThresholdBaseMoveDecider implements MoveDecider {
+    private final ThresholdEvaluator evaluator;
+
+    public ThresholdBaseMoveDecider(ThresholdEvaluator evaluator) {
+        this.evaluator = evaluator;
+    }
+
+    @Override
+    public boolean canMove(int randomNumber){
+        return evaluator.isSatisfied(randomNumber);
+    }
+}

src/main/java/racinggame/model/car/policy/evaluator/GreaterThanOrEqualThresholdEvaluator.java

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+package racinggame.model.car.policy.evaluator;
+
+public class GreaterThanOrEqualThresholdEvaluator implements ThresholdEvaluator {
+    private final int threshold;
+
+    public GreaterThanOrEqualThresholdEvaluator(int threshold) {
+        this.threshold = threshold;
+    }
+    @Override
+    public boolean isSatisfied(int value){
+        return value >= threshold;
+    }
+}

src/main/java/racinggame/model/car/policy/evaluator/ThresholdEvaluator.java

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+package racinggame.model.car.policy.evaluator;
+
+public interface ThresholdEvaluator {
+    boolean isSatisfied(int value);
+}

src/main/java/racinggame/model/car/policy/numbergenerator/RandomGenerator.java

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+package racinggame.model.car.policy.numbergenerator;
+
+public interface RandomGenerator {
+    int generate();
+}

src/main/java/racinggame/model/car/policy/numbergenerator/ZeroToNineRandomGenerator.java

@@ -0,0 +1,11 @@
+package racinggame.model.car.policy.numbergenerator;
+import java.util.Random;
+
+public class ZeroToNineRandomGenerator implements RandomGenerator {
+    private final Random random=new Random();
+
+    @Override
+    public int generate() {
+        return random.nextInt(10);
+    }
+}

src/main/java/racinggame/model/car/policy/strategy/MoveStrategy.java

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+package racinggame.model.car.policy.strategy;
+
+public interface MoveStrategy {
+    int addStepSize();
+}

src/main/java/racinggame/model/car/policy/strategy/OneStepMoveStrategy.java

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+package racinggame.model.car.policy.strategy;
+
+import racinggame.model.car.policy.numbergenerator.RandomGenerator;
+import racinggame.model.car.policy.decider.MoveDecider;
+
+public class OneStepMoveStrategy implements MoveStrategy {
+    private static final int STEP_SIZE = 1;
+
+    private final RandomGenerator randomGenerator;
+    private final MoveDecider moveDecider;
+
+    public OneStepMoveStrategy(RandomGenerator randomGenerator, MoveDecider moveDecider) {
+        this.randomGenerator = randomGenerator;
+        this.moveDecider = moveDecider;
+    }
+    @Override
+    public int addStepSize(){
+        int randomNumber=randomGenerator.generate();
+        if(moveDecider.canMove(randomNumber)){
+            return STEP_SIZE;
+        }
+        return 0;
+    }
+}

src/main/java/racinggame/view/InputView.java

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+package racinggame.view;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Scanner;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+public class InputView {
+    private static final String DELIMITER = ",";
+    private static final String CAR_NAME_INPUT_PROMPT ="경주할 자동차 이름을 입력하세요(이름은 쉼표(,)를 기준으로 구분).";
+
+    public static List<String> readCarNames() {
+        Scanner scanner = new Scanner(System.in);
+        System.out.println(CAR_NAME_INPUT_PROMPT);
+
+        List<String> names = Arrays.stream(scanner.nextLine().split(DELIMITER))
+                .map(String::trim)
+                .toList();
+
+        if (names.stream().anyMatch(name -> name.length() > 5)) {
+            throw new IllegalArgumentException("이름은 5자 이하만 가능합니다.");
+        }
+
+        Set<String> unique = names.stream().collect(Collectors.toSet());
+        if (unique.size() != names.size()) {
+            throw new IllegalArgumentException("자동차 이름은 모두 고유해야 합니다.");
+        }
+
+        return names;
+    }
+
+    public static int readMoveCount() {
+        Scanner scanner = new Scanner(System.in);
+        System.out.println("시도할 회수는 몇회인가요?");
+
+        int moveCount = scanner.nextInt();
+        if (moveCount <= 0) {
+            throw new IllegalArgumentException("moveCount는 0보다 큰 값이여야 합니다.");
+        }
+
+        return moveCount;
+    }
+}

src/main/java/racinggame/view/OutputView.java

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+package racinggame.view;
+
+import racinggame.model.car.Car;
+
+import java.util.List;
+
+public class OutputView {
+    public static void printResult(List<Car> cars) {
+        System.out.println("\n실행 결과");
+        for (Car car : cars) {
+            System.out.println(car.getName() + " : " + "-".repeat(car.getMovedDistance()));
+        }
+        System.out.println();
+    }
+
+    public static void printWinner(List<String> winners) {
+        System.out.println(String.join(", ", winners) + "가 최종 우승했습니다.");
+    }
+
+}