feat: 저장소 구현체, 메시지를 담을 클래스 구현

Author: wonu606

calculator/src/main/java/com/wonu606/calculator/CalculatorApp.java

@@ -2,9 +2,11 @@
 
 import com.wonu606.app.App;
 import com.wonu606.calculator.storage.Persistence;
+import com.wonu606.calculator.storage.ResultStore;
 import com.wonu606.calculator.strategy.Strategy;
 import com.wonu606.io.Input;
 import com.wonu606.io.Print;
+import com.wonu606.util.Message;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
@@ -13,7 +15,7 @@
 public class CalculatorApp implements App {
 
     private final List<Strategy> strategies = new ArrayList<>();
-    private final Persistence store;
+    private final Persistence store = new ResultStore();
     Input input;
     Print printer;
 

calculator/src/main/java/com/wonu606/calculator/storage/ResultStore.java

@@ -0,0 +1,36 @@
+package com.wonu606.calculator.storage;
+
+import com.wonu606.calculator.model.CalculationResult;
+import com.wonu606.util.Message;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+public class ResultStore implements Persistence {
+
+    private final List<CalculationResult> store = new ArrayList<>();
+
+    @Override
+    public void saveResult(CalculationResult calculationResult) {
+        store.add(calculationResult);
+    }
+
+    @Override
+    public CalculationResult findResult(int sequence) {
+        try {
+            return store.get(sequence - 1);
+        } catch (IndexOutOfBoundsException exception) {
+            throw new IllegalArgumentException(Message.INVALID_ORDER);
+        }
+    }
+
+    @Override
+    public List<CalculationResult> findAllResult() {
+        return new ArrayList<>(store);
+    }
+
+    @Override
+    public void clear() {
+        store.clear();
+    }
+}

calculator/src/main/java/com/wonu606/util/Message.java

@@ -0,0 +1,6 @@
+package com.wonu606.util;
+
+public abstract class Message {
+    public static final String INVALID_ORDER = "잘못된 순번입니다.";
+    public static final String INVALID_NUMBER = "잘못된 번호입니다.";
+}

calculator/src/test/java/com/wonu606/storage/ResultStoreTest.java

@@ -5,19 +5,20 @@
 
 import com.wonu606.calculator.model.CalculationResult;
 import com.wonu606.calculator.storage.Persistence;
+import com.wonu606.calculator.storage.ResultStore;
+import com.wonu606.util.Message;
 import java.util.ArrayList;
 import java.util.List;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 
 public class ResultStoreTest {
-
     @Test
     @DisplayName("저장")
     void testSave() {
         // given
-        Persistence store;
+        Persistence store = new ResultStore();
 
         // when
         CalculationResult calculationResult = new CalculationResult("2 + 2", 4.0d);
@@ -31,7 +32,7 @@ void testSave() {
     @DisplayName("순서로 결과 찾기")
     void testFind() {
         // given
-        Persistence store;
+        Persistence store = new ResultStore();
 
         // when
         CalculationResult saveResult = new CalculationResult("5 + 10", 15.0d);
@@ -46,7 +47,7 @@ void testFind() {
     @DisplayName("1 미만의 수로 찾은 경우 예외 발생")
     void testFindNumberLessThan1() {
         // given
-        Persistence store;
+        Persistence store = new ResultStore();
 
         // then
         CalculationResult saveResult = new CalculationResult("5 + 10", 15.0d);
@@ -55,14 +56,14 @@ void testFindNumberLessThan1() {
         // then
         assertThatThrownBy(() -> store.findResult(0))
                 .isInstanceOf(IllegalArgumentException.class)
-                .hasMessageContaining("잘못된 순번입니다.");
+                .hasMessageContaining(Message.INVALID_ORDER);
     }
 
     @Test
     @DisplayName("사이즈 초과의 수로 찾은 경우 예외 발생")
     void testFindNumberMoreThanSize() {
         // given
-        Persistence store;
+        Persistence store = new ResultStore();
 
         // when
         CalculationResult saveResult = new CalculationResult("5 + 10", 15.0d);
@@ -71,14 +72,14 @@ void testFindNumberMoreThanSize() {
         // then
         assertThatThrownBy(() -> store.findResult(store.findAllResult().size() + 1))
                 .isInstanceOf(IllegalArgumentException.class)
-                .hasMessageContaining("잘못된 순번입니다.");
+                .hasMessageContaining(Message.INVALID_ORDER);
     }
 
     @Test
     @DisplayName("모두 찾기")
     void testFindAll() {
         // given
-        Persistence store;
+        Persistence store = new ResultStore();
 
         // when
         List<CalculationResult> results = new ArrayList<>();
@@ -100,7 +101,7 @@ void testFindAll() {
     @DisplayName("클리어")
     void testClear() {
         // given
-        Persistence store;
+        Persistence store = new ResultStore();
 
         // when
         store.saveResult(new CalculationResult("11 + 6", 17.0d));