修复AbstractCacheputWithoutLock方法可能导致的外部资源泄露问题（pr#3958@Github）

hutool-core/src/main/java/org/dromara/hutool/core/cache/impl/AbstractCache.java

@@ -107,7 +107,9 @@ public abstract class AbstractCache<K, V> implements Cache<K, V> {
 		final MutableObj<K> mKey = MutableObj.of(key);
 
 		// issue#3618 对于替换的键值对，不做满队列检查和清除
-		if (cacheMap.containsKey(mKey)) {
+		final CacheObj<K, V> oldObj = cacheMap.get(mKey);
+		if (null != oldObj) {
+			onRemove(oldObj.key, oldObj.obj);
 			// 存在相同key，覆盖之
 			cacheMap.put(mKey, co);
 		} else {

hutool-core/src/main/java/org/dromara/hutool/core/cache/impl/LockedCache.java

@@ -17,8 +17,11 @@
 package org.dromara.hutool.core.cache.impl;
 
 import org.dromara.hutool.core.collection.iter.CopiedIter;
+import org.dromara.hutool.core.collection.set.SetUtil;
+import org.dromara.hutool.core.lang.mutable.Mutable;
 
 import java.util.Iterator;
+import java.util.Set;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
 
@@ -98,7 +101,14 @@ public abstract class LockedCache<K, V> extends AbstractCache<K, V> {
 	public void clear() {
 		lock.lock();
 		try {
-			cacheMap.clear();
+			// 获取所有键的副本
+			final Set<Mutable<K>> keys = SetUtil.of(cacheMap.keySet());
+			for (final Mutable<K> key : keys) {
+				final CacheObj<K, V> co = removeWithoutLock(key.get());
+				if (co != null) {
+					onRemove(co.key, co.obj); // 触发资源释放
+				}
+			}
 		} finally {
 			lock.unlock();
 		}

hutool-core/src/test/java/org/dromara/hutool/core/cache/CacheTest.java

@@ -164,4 +164,22 @@ public class CacheTest {
 		assertFalse(ALARM_CACHE.containsKey(1));
 		assertEquals(1, counter.get());
 	}
+
+	/**
+	 * ReentrantCache类clear()方法、AbstractCache.putWithoutLock方法可能导致资源泄露
+	 * https://github.com/chinabugotech/hutool/issues/3957
+	 */
+	@Test
+	public void reentrantCache_clear_Method_Test() {
+		final AtomicInteger removeCount = new AtomicInteger();
+		final Cache<String, String> lruCache = CacheUtil.newLRUCache(4);
+		lruCache.setListener((key, cachedObject) -> removeCount.getAndIncrement());
+		lruCache.put("key1","String1");
+		lruCache.put("key2","String2");
+		lruCache.put("key3","String3");
+		lruCache.put("key1","String4");//key已经存在，原始putWithoutLock方法存在资源泄露
+		lruCache.put("key4","String5");
+		lruCache.clear();//ReentrantCache类clear()方法存在资源泄露
+		Assertions.assertEquals(5, removeCount.get());
+	}
 }