feat: 체이닝을 사용한 테이블 구현

Author: ksundong

yoonexample/src/main/java/table/chainedtable/ChainedHashTable.java

@@ -0,0 +1,68 @@
+package table.chainedtable;
+
+import list.DummyLinkedList;
+import list.List;
+import table.HashFunction;
+import table.Table;
+
+public class ChainedHashTable<K, V> implements Table<K, V> {
+
+  private final List<ChainedSlot<K, V>>[] slots;
+  private final HashFunction<K> hashFunction;
+
+  public ChainedHashTable(HashFunction<K> hashFunction) {
+    this(100, hashFunction);
+  }
+
+  public ChainedHashTable(int slotSize, HashFunction<K> hashFunction) {
+    this.slots = new List[slotSize];
+    this.hashFunction = hashFunction;
+  }
+
+  @Override
+  public void insert(K key, V value) {
+    if (search(key) != null) {
+      System.out.println("키 중복");
+      return;
+    }
+
+    List<ChainedSlot<K, V>> slotList = this.slots[hashFunction.hashFunction(key)];
+    ChainedSlot<K, V> slot = new ChainedSlot<>(key, value);
+    if (slotList == null) {
+      this.slots[hashFunction.hashFunction(key)] = new DummyLinkedList<>();
+      slotList = this.slots[hashFunction.hashFunction(key)];
+    }
+    slotList.insert(slot);
+  }
+
+  @Override
+  public V search(K key) {
+    List<ChainedSlot<K, V>> slotList = this.slots[hashFunction.hashFunction(key)];
+    if (slotList == null || slotList.isEmpty()) {
+      return null;
+    }
+
+    for (int i = 0; i < slotList.size(); i++) {
+      ChainedSlot<K, V> slot = slotList.get(i);
+      if (key.equals(slot.getKey())) {
+        return slot.getValue();
+      }
+    }
+    return null;
+  }
+
+  @Override
+  public V delete(K key) {
+    List<ChainedSlot<K, V>> slotList = this.slots[hashFunction.hashFunction(key)];
+    if (slotList == null || slotList.isEmpty()) {
+      return null;
+    }
+
+    for (int i = 0; i < slotList.size(); i++) {
+      if (key.equals(slotList.get(i).getKey())) {
+        return slotList.remove(i).getValue();
+      }
+    }
+    return null;
+  }
+}

yoonexample/src/main/java/table/chainedtable/ChainedSlot.java

@@ -0,0 +1,20 @@
+package table.chainedtable;
+
+public class ChainedSlot<K, V> {
+
+  private final K key;
+  private final V value;
+
+  public ChainedSlot(K key, V value) {
+    this.key = key;
+    this.value = value;
+  }
+
+  public V getValue() {
+    return this.value;
+  }
+
+  public K getKey() {
+    return this.key;
+  }
+}

yoonexample/src/test/java/table/TableTest.java

@@ -7,6 +7,7 @@
 import org.assertj.core.util.Lists;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
+import table.chainedtable.ChainedHashTable;
 
 class TableTest {
 
@@ -92,6 +93,21 @@ void setUp() {
     }
   }
 
+  @Test
+  void 체이닝_테이블_중복_탐색_테스트() {
+    hashFunction = key -> 0;
+    table = new ChainedHashTable<>(hashFunction);
+    for (Person person : persons) {
+      table.insert(person.getId(), person);
+    }
+
+    Person searchedPerson;
+    for (Person targetPerson : persons) {
+      searchedPerson = table.search(targetPerson.getId());
+      assertThat(searchedPerson).isNotNull().isEqualToComparingFieldByField(targetPerson);
+    }
+  }
+
   @Test
   void 체이닝_테이블_삭제_테스트() {
     table = new ChainedHashTable<>(hashFunction);