[java-lotto] yohan.kim(김요한) 과제 제출합니다.

docs/README.md

@@ -0,0 +1,22 @@
+## 기능 목록
+
+- [x] 로또 Lotto
+  - [x] 여섯 개인지 검증 - validateCounts()
+  - [x] 로또 번호에 중복된 숫자가 있는지 검증 - validateDuplication()
+  - [x] 정답과 비교 후 등수 반환 - calculateRank()
+    - [x] 3항 연산자 제거
+- [x] 로또 판매기 Seller
+  - [x] 금액에 받아 구매 가능한 로또 개수 반환 - calculateLottoCount()
+  - [x] 로또 발행 - getLotto()
+    - [x] 오름차순으로 발행
+  - [x] 개수만큼 로또 발행 - getLottos()
+  - [x] 로또 당첨 통계 반환 - getResult()
+  - [x] 수익률 계산 - calculateRate()
+    - [x] 수익률은 소수점 둘째자리에서 반올림
+- [x] UI
+  - [x] 구입금액 입력받기 - receivePurchaseMoney()
+  - [x] 구매한 로또 출력 - printBoughtLottos()
+  - [x] 당첨 번호 입력받기 - receiveAnswers()
+  - [x] 보너스 번호 입력받기 - receiveBonus()
+  - [x] 당첨 통계 출력 - printResult()
+  - [x] 수익률 출력 - printRate()

src/main/java/lotto/Application.java

@@ -1,7 +1,31 @@
 package lotto;
 
+import java.util.List;
+
 public class Application {
+
+    public static final int LOTTO_PRICE = 1_000;
+
     public static void main(String[] args) {
-        // TODO: 프로그램 구현
+
+        String purchaseMoneyStr = UI.receivePurchaseMoney();
+        Seller seller = new Seller(LOTTO_PRICE);
+
+        try {
+            int purchaseCount = seller.calculateLottoCount(seller.parsePurchaseMoneyStr(purchaseMoneyStr));
+
+            List<Lotto> lottos = seller.getLottos(purchaseCount);
+            UI.printBoughtLottos(lottos);
+
+            List<Integer> answers = UI.receiveAnswers();
+            int bonus = UI.receiveBonus();
+
+            List<Integer> result = seller.getResult(lottos, answers, bonus);
+            UI.printResult(result);
+            UI.printRate(seller.calculateRate(result, purchaseCount));
+        } catch (IllegalArgumentException e) {
+            UI.handlingIllegalArgumentException(e);
+        }
+
     }
 }

src/main/java/lotto/Lotto.java

@@ -1,6 +1,9 @@
 package lotto;
 
+import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 public class Lotto {
     private final List<Integer> numbers;
@@ -11,10 +14,59 @@ public Lotto(List<Integer> numbers) {
     }
 
     private void validate(List<Integer> numbers) {
+        validateCounts(numbers);
+        validateDuplication(numbers);
+    }
+
+    private void validateCounts(List<Integer> numbers) {
         if (numbers.size() != 6) {
-            throw new IllegalArgumentException();
+            throw new IllegalArgumentException("로또 번호의 개수는 6개여야 합니다.");
+        }
+    }
+
+    private void validateDuplication(List<Integer> numbers) {
+        if (new HashSet<>(numbers).size() != numbers.size()) {
+            throw new IllegalArgumentException("로또 번호는 중복되어선 안됩니다.");
+        }
+    }
+
+    public int calculateRank(List<Integer> answers, int bonus) {
+
+        Set<Integer> set = new HashSet<>(numbers);
+
+        int correct = getCorrect(answers, set);
+        int bonusCorrect = getBonusCorrect(bonus, set, correct);
+
+        return rankByCondition(correct, bonusCorrect);
+    }
+
+    private static int getCorrect(List<Integer> answers, Set<Integer> set) {
+        return (int) answers.stream()
+                .filter(set::contains)
+                .count();
+    }
+
+    private static int getBonusCorrect(int bonus, Set<Integer> set, int correct) {
+        if (set.contains(bonus) && correct == 5) {
+            return 1;
         }
+        return 0;
     }
 
-    // TODO: 추가 기능 구현
+    private int rankByCondition(int correct, int bonusCorrect) {
+        if (correct == 6) {
+            return 1;
+        }
+
+        if (correct + bonusCorrect <= 2) {
+            return 6;
+        }
+
+        return 8 - (correct + bonusCorrect);
+    }
+
+    @Override
+    public String toString() {
+        return numbers.toString();
+    }
 }

src/main/java/lotto/Seller.java

@@ -0,0 +1,65 @@
+package lotto;
+
+import camp.nextstep.edu.missionutils.Randoms;
+
+import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+public class Seller {
+
+    private final int lottoPrice;
+    private static final List<Integer> prize = List.of(2_000_000_000, 30_000_000, 1_500_000, 50_000, 5_000, 0);
+
+    public Seller(int lottoPrice) {
+        this.lottoPrice = lottoPrice;
+    }
+
+    public int parsePurchaseMoneyStr(String purchaseMoneyStr) {
+        try {
+            return Integer.parseInt(purchaseMoneyStr);
+        } catch (NumberFormatException e) {
+            throw new IllegalArgumentException("입력은 1000으로 나눠지는 값이어야 합니다.");
+        }
+    }
+
+    public int calculateLottoCount(int money) {
+        return money / lottoPrice;
+    }
+
+    public Lotto getLotto() {
+        List<Integer> randoms = new ArrayList<>(Randoms.pickUniqueNumbersInRange(1, 45, 6));
+        Collections.sort(randoms);
+        return new Lotto(randoms);
+    }
+
+    public List<Lotto> getLottos(int count) {
+        return IntStream.range(0, count)
+                .mapToObj(i -> getLotto())
+                .collect(Collectors.toList());
+    }
+
+    public List<Integer> getResult(List<Lotto> lottos, List<Integer> answers, int bonus) {
+        List<Integer> result = new ArrayList<>(List.of(0, 0, 0, 0, 0, 0));
+
+        for (Lotto lotto: lottos) {
+            int index = lotto.calculateRank(answers, bonus) - 1;
+            result.set(index, result.get(index) + 1);
+        }
+        return result;
+    }
+
+    public BigDecimal calculateRate(List<Integer> ranks, int count) {
+
+        long prizeSum = IntStream.range(0, 6)
+                .mapToLong(index -> (long) ranks.get(index) * prize.get(index))
+                .sum();
+        int cost = lottoPrice * count;
+
+        double rate = prizeSum * 100 / (double) cost;
+        return new BigDecimal(rate).setScale(1, BigDecimal.ROUND_HALF_UP);
+    }
+}

src/main/java/lotto/UI.java

@@ -0,0 +1,62 @@
+package lotto;
+
+import camp.nextstep.edu.missionutils.Console;
+
+import java.math.BigDecimal;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+public class UI {
+
+    private static final Map<Integer, String> resultOutputByRank = Map.of(
+            1, "6개 일치 (2,000,000,000원)",
+            2, "5개 일치, 보너스 볼 일치 (30,000,000원)",
+            3, "5개 일치 (1,500,000원)",
+            4, "4개 일치 (50,000원)",
+            5, "3개 일치 (5,000원)"
+    );
+
+    public static String receivePurchaseMoney() {
+        System.out.println("구입금액을 입력해 주세요.");
+        return Console.readLine();
+    }
+
+    public static void printBoughtLottos(List<Lotto> lottos) {
+        System.out.println("\n" + lottos.size() + "개를 구매했습니다.");
+        for (Lotto lotto : lottos) {
+            System.out.println(lotto);
+        }
+    }
+
+    public static List<Integer> receiveAnswers() {
+        System.out.println("\n당첨 번호를 입력해 주세요.");
+        String[] split = Console.readLine().split(",");
+        return Arrays.stream(split)
+                .map(Integer::parseInt)
+                .collect(Collectors.toList());
+    }
+
+    public static int receiveBonus() {
+        System.out.println("\n보너스 번호를 입력해 주세요.");
+        return Integer.parseInt(Console.readLine());
+    }
+
+    public static void printResult(List<Integer> result) {
+        System.out.println("\n당첨 통계");
+        System.out.println("---");
+
+        for (int index = 4; index >= 0; index--) {
+            System.out.println(resultOutputByRank.get(index + 1) + " - " + result.get(index) + "개");
+        }
+    }
+
+    public static void printRate(BigDecimal rate) {
+        System.out.println("총 수익률은 " + rate.toPlainString() + "%입니다.");
+    }
+
+    public static void handlingIllegalArgumentException(IllegalArgumentException e) {
+        System.out.println("[ERROR] " + e.getMessage());
+    }
+}

src/test/java/lotto/LottoTest.java

@@ -1,10 +1,12 @@
 package lotto;
 
+import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 
 import java.util.List;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 class LottoTest {
@@ -18,10 +20,97 @@ void createLottoByOverSize() {
     @DisplayName("로또 번호에 중복된 숫자가 있으면 예외가 발생한다.")
     @Test
     void createLottoByDuplicatedNumber() {
-        // TODO: 이 테스트가 통과할 수 있게 구현 코드 작성
         assertThatThrownBy(() -> new Lotto(List.of(1, 2, 3, 4, 5, 5)))
                 .isInstanceOf(IllegalArgumentException.class);
     }
 
-    // 아래에 추가 테스트 작성 가능
+    @DisplayName("6개 일치하면, 1을 반환한다.")
+    @Test
+    void calculateRank_1st() {
+        //given
+        Lotto lotto = new Lotto(List.of(1, 2, 3, 4, 5, 6));
+        List<Integer> answers = List.of(1, 2, 3, 4, 5, 6);
+        int bonus = 7;
+
+        //when
+        int rank = lotto.calculateRank(answers, bonus);
+
+        //then
+        assertThat(rank).isEqualTo(1);
+    }
+
+    @DisplayName("5개 일치하고, 보너스 볼 일치하면, 2을 반환한다.")
+    @Test
+    void calculateRank_2nd() {
+        //given
+        Lotto lotto = new Lotto(List.of(1, 2, 3, 4, 5, 7));
+        List<Integer> answers = List.of(1, 2, 3, 4, 5, 6);
+        int bonus = 7;
+
+        //when
+        int rank = lotto.calculateRank(answers, bonus);
+
+        //then
+        assertThat(rank).isEqualTo(2);
+    }
+
+    @DisplayName("5개 일치하면, 3을 반환한다.")
+    @Test
+    void calculateRank_3rd() {
+        //given
+        Lotto lotto = new Lotto(List.of(1, 2, 3, 4, 5, 8));
+        List<Integer> answers = List.of(1, 2, 3, 4, 5, 6);
+        int bonus = 7;
+
+        //when
+        int rank = lotto.calculateRank(answers, bonus);
+
+        //then
+        assertThat(rank).isEqualTo(3);
+    }
+
+    @DisplayName("4개 일치하면, 4을 반환한다.")
+    @Test
+    void calculateRank_4th() {
+        //given
+        Lotto lotto = new Lotto(List.of(1, 2, 3, 4, 7, 8));
+        List<Integer> answers = List.of(1, 2, 3, 4, 5, 6);
+        int bonus = 7;
+
+        //when
+        int rank = lotto.calculateRank(answers, bonus);
+
+        //then
+        assertThat(rank).isEqualTo(4);
+    }
+
+    @DisplayName("3개 일치하면, 5을 반환한다.")
+    @Test
+    void calculateRank_5th() {
+        //given
+        Lotto lotto = new Lotto(List.of(1, 2, 3, 7, 8, 9));
+        List<Integer> answers = List.of(1, 2, 3, 4, 5, 6);
+        int bonus = 7;
+
+        //when
+        int rank = lotto.calculateRank(answers, bonus);
+
+        //then
+        assertThat(rank).isEqualTo(5);
+    }
+
+    @DisplayName("2개 이하 일치하면, 6을 반환한다.")
+    @Test
+    void calculateRank_6th() {
+        //given
+        Lotto lotto = new Lotto(List.of(1, 2, 7, 8, 9, 10));
+        List<Integer> answers = List.of(1, 2, 3, 4, 5, 6);
+        int bonus = 7;
+
+        //when
+        int rank = lotto.calculateRank(answers, bonus);
+
+        //then
+        assertThat(rank).isEqualTo(6);
+    }
 }