숫자 야구 게임 [sjiwon]

docs/README.md

@@ -15,9 +15,9 @@
 ### `Baseballs`
 - 입력한 3개의 숫자들을 추상화시킨 `Baseballs`
     - Baseballs에 속한 `List<Integer>`은
-        - [ ] 각 원소가 `1..9` 범위 사이여야 한다
-        - [ ] 원소의 크기가 3이여야 한다
-        - [ ] 중복된 원소가 없어야 한다
+        - [X] 각 원소가 `1..9` 범위 사이여야 한다
+        - [X] 원소의 크기가 3이여야 한다
+        - [X] 중복된 원소가 없어야 한다
 
 <br>
 

src/main/java/baseball/model/Baseballs.java

@@ -0,0 +1,51 @@
+package baseball.model;
+
+import java.util.Collections;
+import java.util.List;
+
+import static baseball.utils.BaseballConstants.*;
+import static baseball.utils.ExceptionConstants.BaseballException.*;
+
+public class Baseballs {
+    private final List<Integer> baseballs;
+
+    public Baseballs(final List<Integer> baseballs) {
+        validateEachBaseballElementIsInRange(baseballs);
+        validateTotalBaseballSize(baseballs);
+        validateBaseballHasDuplicateNumber(baseballs);
+        this.baseballs = baseballs;
+    }
+
+    private void validateEachBaseballElementIsInRange(final List<Integer> baseballs) {
+        if (hasOutOfRange(baseballs)) {
+            throw new IllegalArgumentException(BASEBALL_IS_NOT_IN_RANGE.message);
+        }
+    }
+
+    private boolean hasOutOfRange(final List<Integer> baseballs) {
+        return baseballs.stream()
+                .anyMatch(baseball -> baseball < MIN_BASEBALL || baseball > MAX_BASEBALL);
+    }
+
+    private void validateTotalBaseballSize(final List<Integer> baseballs) {
+        if (baseballs.size() != BASEBALL_SIZE) {
+            throw new IllegalArgumentException(BASEBALL_SIZE_IS_NOT_FULFILL.message);
+        }
+    }
+
+    private void validateBaseballHasDuplicateNumber(final List<Integer> baseballs) {
+        if (hasDuplicateNumber(baseballs)) {
+            throw new IllegalArgumentException(BASEBALL_MUST_BE_UNIQUE.message);
+        }
+    }
+
+    private boolean hasDuplicateNumber(final List<Integer> baseballs) {
+        return baseballs.stream()
+                .distinct()
+                .count() != BASEBALL_SIZE;
+    }
+
+    public List<Integer> getBaseballs() {
+        return Collections.unmodifiableList(baseballs);
+    }
+}

src/main/java/baseball/utils/ExceptionConstants.java

@@ -0,0 +1,16 @@
+package baseball.utils;
+
+public class ExceptionConstants {
+    public enum BaseballException {
+        BASEBALL_IS_NOT_IN_RANGE("숫자는 1..9 범위만 허용합니다."),
+        BASEBALL_SIZE_IS_NOT_FULFILL("숫자 3개를 입력해주세요."),
+        BASEBALL_MUST_BE_UNIQUE("중복된 숫자는 허용하지 않습니다."),
+        ;
+
+        public final String message;
+
+        BaseballException(final String message) {
+            this.message = message;
+        }
+    }
+}