fix bug

CHANGELOG.md

@@ -13,6 +13,7 @@
 * 【core   】     修复setter重载导致匹配错误（issue#2082@Github）
 * 【core   】     修复RegexPool汉字匹配范围小问题（pr#2081@Github）
 * 【core   】     修复OS中的拼写错误（pr#500@Gitee）
+* 【core   】     修复CustomKeyMap的merge失效问题（issue#2086@Github）
 
 -------------------------------------------------------------------------------------------------------------
 # 5.7.19 (2022-01-07)

hutool-core/src/main/java/cn/hutool/core/map/CustomKeyMap.java

@@ -1,6 +1,7 @@
 package cn.hutool.core.map;
 
 import java.util.Map;
+import java.util.function.BiFunction;
 
 /**
  * 自定义键的Map，默认HashMap实现
@@ -67,6 +68,31 @@ public abstract class CustomKeyMap<K, V> extends MapWrapper<K, V> {
 		return super.replace((K) customKey(key), value);
 	}
 
+	//---------------------------------------------------------------------------- Override default methods start
+	@Override
+	public V getOrDefault(Object key, V defaultValue) {
+		return super.getOrDefault(customKey(key), defaultValue);
+	}
+
+	@Override
+	public V computeIfPresent(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
+		//noinspection unchecked
+		return super.computeIfPresent((K) customKey(key), remappingFunction);
+	}
+
+	@Override
+	public V compute(K key, BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
+		//noinspection unchecked
+		return super.compute((K) customKey(key), remappingFunction);
+	}
+
+	@Override
+	public V merge(K key, V value, BiFunction<? super V, ? super V, ? extends V> remappingFunction) {
+		//noinspection unchecked
+		return super.merge((K) customKey(key), value, remappingFunction);
+	}
+	//---------------------------------------------------------------------------- Override default methods end
+
 	/**
 	 * 自定义键
 	 *

hutool-core/src/main/java/cn/hutool/core/map/MapWrapper.java

@@ -16,7 +16,6 @@ import java.util.function.Function;
  * @param <K> 键类型
  * @param <V> 值类型
  * @author looly
- * @author looly
  * @since 4.3.3
  */
 public class MapWrapper<K, V> implements Map<K, V>, Iterable<Map.Entry<K, V>>, Serializable, Cloneable {
@@ -179,6 +178,7 @@ public class MapWrapper<K, V> implements Map<K, V>, Iterable<Map.Entry<K, V>>, S
 		return raw.computeIfAbsent(key, mappingFunction);
 	}
 
+	// 重写默认方法的意义在于，如果被包装的Map自定义了这些默认方法，包装类就可以保持这些行为的一致性
 	//---------------------------------------------------------------------------- Override default methods start
 	@Override
 	public V getOrDefault(Object key, V defaultValue) {

hutool-core/src/test/java/cn/hutool/core/map/CaseInsensitiveMapTest.java

@@ -1,10 +1,11 @@
 package cn.hutool.core.map;
 
+import cn.hutool.core.lang.Pair;
 import org.junit.Assert;
 import org.junit.Test;
 
 public class CaseInsensitiveMapTest {
-	
+
 	@Test
 	public void caseInsensitiveMapTest() {
 		CaseInsensitiveMap<String, String> map = new CaseInsensitiveMap<>();
@@ -12,7 +13,7 @@ public class CaseInsensitiveMapTest {
 		Assert.assertEquals("OK", map.get("aaa"));
 		Assert.assertEquals("OK", map.get("AAA"));
 	}
-	
+
 	@Test
 	public void caseInsensitiveLinkedMapTest() {
 		CaseInsensitiveLinkedMap<String, String> map = new CaseInsensitiveLinkedMap<>();
@@ -20,4 +21,16 @@ public class CaseInsensitiveMapTest {
 		Assert.assertEquals("OK", map.get("aaa"));
 		Assert.assertEquals("OK", map.get("AAA"));
 	}
+
+	@Test
+	public void mergeTest(){
+		//https://github.com/dromara/hutool/issues/2086
+		Pair<String, String> b = new Pair<>("a", "value");
+		Pair<String, String> a = new Pair<>("A", "value");
+		final CaseInsensitiveMap<Object, Object> map = new CaseInsensitiveMap<>();
+		map.merge(b.getKey(), b.getValue(), (A, B) -> A);
+		map.merge(a.getKey(), a.getValue(), (A, B) -> A);
+
+		Assert.assertEquals(1, map.size());
+	}
 }