refactoring : middle man - replace superclass with delegate

refactoring/src/main/java/com/example/refactoring/_18_middle_man/_39_replace_superclass_with_delegate/CategoryItem.java

@@ -0,0 +1,30 @@
+package com.example.refactoring._18_middle_man._39_replace_superclass_with_delegate;
+
+import java.util.List;
+
+public class CategoryItem {
+
+    private Integer id;
+
+    private String title;
+
+    private List<String> tags;
+
+    public CategoryItem(Integer id, String title, List<String> tags) {
+        this.id = id;
+        this.title = title;
+        this.tags = tags;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public boolean hasTag(String tag) {
+        return this.tags.contains(tag);
+    }
+}

refactoring/src/main/java/com/example/refactoring/_18_middle_man/_39_replace_superclass_with_delegate/Scroll.java

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+package com.example.refactoring._18_middle_man._39_replace_superclass_with_delegate;
+
+import java.time.LocalDate;
+import java.time.temporal.ChronoUnit;
+import java.util.List;
+
+public class Scroll {
+
+    private LocalDate dateLastCleaned;
+
+    private CategoryItem categoryItem;
+
+    public Scroll(Integer id, String title, List<String> tags, LocalDate dateLastCleaned) {
+        this.dateLastCleaned = dateLastCleaned;
+        this.categoryItem = new CategoryItem(id, title, tags);
+    }
+
+    public long daysSinceLastCleaning(LocalDate targetDate) {
+        return this.dateLastCleaned.until(targetDate, ChronoUnit.DAYS);
+    }
+}

refactoring/src/main/java/com/example/refactoring/_18_middle_man/_39_replace_superclass_with_delegate/_before/CategoryItem.java

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+package com.example.refactoring._18_middle_man._39_replace_superclass_with_delegate._before;
+
+import java.util.List;
+
+public class CategoryItem {
+
+    private Integer id;
+
+    private String title;
+
+    private List<String> tags;
+
+    public CategoryItem(Integer id, String title, List<String> tags) {
+        this.id = id;
+        this.title = title;
+        this.tags = tags;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public boolean hasTag(String tag) {
+        return this.tags.contains(tag);
+    }
+}

refactoring/src/main/java/com/example/refactoring/_18_middle_man/_39_replace_superclass_with_delegate/_before/Scroll.java

@@ -0,0 +1,19 @@
+package com.example.refactoring._18_middle_man._39_replace_superclass_with_delegate._before;
+
+import java.time.LocalDate;
+import java.time.temporal.ChronoUnit;
+import java.util.List;
+
+public class Scroll extends CategoryItem {
+
+    private LocalDate dateLastCleaned;
+
+    public Scroll(Integer id, String title, List<String> tags, LocalDate dateLastCleaned) {
+        super(id, title, tags);
+        this.dateLastCleaned = dateLastCleaned;
+    }
+
+    public long daysSinceLastCleaning(LocalDate targetDate) {
+        return this.dateLastCleaned.until(targetDate, ChronoUnit.DAYS);
+    }
+}

refactoring/src/test/java/com/example/refactoring/_18_middle_man/_39_replace_superclass_with_delegate/ScrollTest.java

@@ -0,0 +1,17 @@
+package com.example.refactoring._18_middle_man._39_replace_superclass_with_delegate;
+
+import org.junit.jupiter.api.Test;
+
+import java.time.LocalDate;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class ScrollTest {
+
+    @Test
+    void daysSinceLastCleaning() {
+        Scroll scroll = new Scroll(1, "kim", null, LocalDate.of(2022, 1, 10));
+        assertEquals(5, scroll.daysSinceLastCleaning(LocalDate.of(2022, 1, 15)));
+    }
+
+}