refactor: centralize thread-local cleanup into ThreadLocalCleaner

fesod-sheet/src/main/java/org/apache/fesod/sheet/analysis/ExcelAnalyserImpl.java

@@ -49,11 +49,8 @@
 import org.apache.fesod.sheet.read.metadata.holder.xls.XlsReadWorkbookHolder;
 import org.apache.fesod.sheet.read.metadata.holder.xlsx.XlsxReadWorkbookHolder;
 import org.apache.fesod.sheet.support.ExcelTypeEnum;
-import org.apache.fesod.sheet.util.ClassUtils;
-import org.apache.fesod.sheet.util.DateUtils;
 import org.apache.fesod.sheet.util.FileUtils;
-import org.apache.fesod.sheet.util.NumberDataFormatterUtils;
-import org.apache.fesod.sheet.util.NumberUtils;
+import org.apache.fesod.sheet.util.ThreadLocalCleaner;
 import org.apache.poi.hssf.OldExcelFormatException;
 import org.apache.poi.hssf.record.crypto.Biff8EncryptionKey;
 import org.apache.poi.poifs.crypt.Decryptor;
@@ -281,23 +278,13 @@ public void finish() {
 
         clearEncrypt03();
 
-        removeThreadLocalCache();
+        ThreadLocalCleaner.clearAllThreadLocals();
 
         if (throwable != null) {
             throw new ExcelAnalysisException("Can not close IO.", throwable);
         }
     }
 
-    /**
-     * Removes thread-local caches used during the analysis process to free up memory.
-     */
-    private void removeThreadLocalCache() {
-        NumberDataFormatterUtils.removeThreadLocalCache();
-        NumberUtils.removeThreadLocalCache();
-        DateUtils.removeThreadLocalCache();
-        ClassUtils.removeThreadLocalCache();
-    }
-
     /**
      * Clears the encryption key for XLS files to ensure secure handling of sensitive data.
      */

fesod-sheet/src/main/java/org/apache/fesod/sheet/context/WriteContextImpl.java

@@ -46,10 +46,8 @@
 import org.apache.fesod.sheet.metadata.property.ExcelContentProperty;
 import org.apache.fesod.sheet.support.ExcelTypeEnum;
 import org.apache.fesod.sheet.util.ClassUtils;
-import org.apache.fesod.sheet.util.DateUtils;
 import org.apache.fesod.sheet.util.FileUtils;
-import org.apache.fesod.sheet.util.NumberDataFormatterUtils;
-import org.apache.fesod.sheet.util.NumberUtils;
+import org.apache.fesod.sheet.util.ThreadLocalCleaner;
 import org.apache.fesod.sheet.util.WorkBookUtil;
 import org.apache.fesod.sheet.util.WriteHandlerUtils;
 import org.apache.fesod.sheet.write.handler.context.CellWriteHandlerContext;
@@ -584,7 +582,7 @@ public void finish(boolean onException) {
             throwable = recordFailure(throwable, t);
         }
         clearEncrypt03();
-        removeThreadLocalCache();
+        ThreadLocalCleaner.clearAllThreadLocals();
         if (throwable != null) {
             throw new ExcelGenerateException("Can not close IO.", throwable);
         }
@@ -606,16 +604,6 @@ private static Throwable recordFailure(Throwable recorded, Throwable t) {
         return recorded;
     }
 
-    /**
-     * Removes thread-local caches used during the write process.
-     */
-    private void removeThreadLocalCache() {
-        NumberDataFormatterUtils.removeThreadLocalCache();
-        NumberUtils.removeThreadLocalCache();
-        DateUtils.removeThreadLocalCache();
-        ClassUtils.removeThreadLocalCache();
-    }
-
     /**
      * Retrieves the current sheet being written.
      *

fesod-sheet/src/main/java/org/apache/fesod/sheet/util/ClassUtils.java

@@ -102,6 +102,14 @@ public class ClassUtils {
     private static final ThreadLocal<Map<ContentPropertyKey, ExcelContentProperty>> CONTENT_THREAD_LOCAL =
             new ThreadLocal<>();
 
+    static {
+        ThreadLocalCleaner.register(() -> {
+            FIELD_THREAD_LOCAL.remove();
+            CLASS_CONTENT_THREAD_LOCAL.remove();
+            CONTENT_THREAD_LOCAL.remove();
+        });
+    }
+
     /**
      * Calculate the configuration information for the class
      *

fesod-sheet/src/main/java/org/apache/fesod/sheet/util/DateUtils.java

@@ -72,6 +72,13 @@ public class DateUtils {
     private static final ThreadLocal<Map<Locale, Map<String, DateTimeFormatter>>> DATE_TIME_FORMATTER_THREAD_LOCAL =
             new ThreadLocal<>();
 
+    static {
+        ThreadLocalCleaner.register(() -> {
+            DATE_FORMAT_THREAD_LOCAL.remove();
+            DATE_TIME_FORMATTER_THREAD_LOCAL.remove();
+        });
+    }
+
     /**
      * The epoch date (1970-01-01) used as the date component when converting
      * {@code java.sql.Time} to {@code LocalDateTime}.

fesod-sheet/src/main/java/org/apache/fesod/sheet/util/ExcelDateFormatDetector.java

@@ -54,6 +54,10 @@ class ExcelDateFormatDetector {
     // for format which start with "年" or "月" or "日" or "时" or "分" or "秒" could be a Chinese date
     private static final Pattern date_ptrn6 = Pattern.compile("(年|月|日|时|分|秒)+");
 
+    static {
+        ThreadLocalCleaner.register(DATE_THREAD_LOCAL::remove);
+    }
+
     private ExcelDateFormatDetector() {}
 
     /**

fesod-sheet/src/main/java/org/apache/fesod/sheet/util/NumberDataFormatterUtils.java

@@ -63,6 +63,10 @@ private boolean matches(boolean use1904windowing, Locale locale, boolean useScie
         }
     }
 
+    static {
+        ThreadLocalCleaner.register(DATA_FORMATTER_THREAD_LOCAL::remove);
+    }
+
     /**
      * Format number data.
      *

fesod-sheet/src/main/java/org/apache/fesod/sheet/util/NumberUtils.java

@@ -56,6 +56,10 @@ public class NumberUtils {
     private static final ThreadLocal<Map<Locale, Map<String, DecimalFormat>>> DECIMAL_FORMAT_THREAD_LOCAL =
             new ThreadLocal<>();
 
+    static {
+        ThreadLocalCleaner.register(DECIMAL_FORMAT_THREAD_LOCAL::remove);
+    }
+
     private NumberUtils() {}
 
     /**

fesod-sheet/src/main/java/org/apache/fesod/sheet/util/ThreadLocalCleaner.java

@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.fesod.sheet.util;
+
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+import lombok.AccessLevel;
+import lombok.NoArgsConstructor;
+import org.apache.commons.lang3.Validate;
+
+/**
+ * Utility class for managing and executing unified {@link ThreadLocal} cleanups.
+ */
+@NoArgsConstructor(access = AccessLevel.PRIVATE)
+public class ThreadLocalCleaner {
+
+    private static final List<Runnable> cleanTasks = new CopyOnWriteArrayList<>();
+
+    /**
+     * Registers a cleanup task.
+     * <p>NOTE: for internal use only.</p>
+     *
+     * @param cleaner the cleanup task to register
+     */
+    public static void register(Runnable cleaner) {
+        Validate.notNull(cleaner, "cleaner cannot be null");
+        cleanTasks.add(cleaner);
+    }
+
+    public static void clearAllThreadLocals() {
+        cleanTasks.forEach(Runnable::run);
+    }
+}

fesod-sheet/src/test/java/org/apache/fesod/sheet/util/ThreadLocalCleanerTest.java

@@ -0,0 +1,72 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.fesod.sheet.util;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Tests {@link ThreadLocalCleaner}.
+ */
+class ThreadLocalCleanerTest {
+
+    @Test
+    void testRegisterNullThrowsException() {
+        Assertions.assertThrows(NullPointerException.class, () -> ThreadLocalCleaner.register(null));
+    }
+
+    @Test
+    void testConcurrentModificationExceptionRegression() throws Exception {
+        CountDownLatch iterationStartedLatch = new CountDownLatch(1);
+        CountDownLatch registrationDoneLatch = new CountDownLatch(1);
+
+        AtomicBoolean task1Executed = new AtomicBoolean(false);
+        AtomicBoolean task2Executed = new AtomicBoolean(false);
+
+        ThreadLocalCleaner.register(() -> {
+            task1Executed.set(true);
+            iterationStartedLatch.countDown();
+            try {
+                if (!registrationDoneLatch.await(5, TimeUnit.SECONDS)) {
+                    throw new IllegalStateException("Timeout waiting for concurrent registration");
+                }
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+            }
+        });
+
+        CompletableFuture<Void> clearFuture = CompletableFuture.runAsync(ThreadLocalCleaner::clearAllThreadLocals);
+
+        Assertions.assertTrue(iterationStartedLatch.await(5, TimeUnit.SECONDS), "Iteration did not start in time");
+
+        ThreadLocalCleaner.register(() -> task2Executed.set(true));
+        registrationDoneLatch.countDown();
+
+        Assertions.assertDoesNotThrow(() -> clearFuture.get(5, TimeUnit.SECONDS));
+        Assertions.assertTrue(task1Executed.get(), "Task 1 should have executed");
+
+        ThreadLocalCleaner.clearAllThreadLocals();
+        Assertions.assertTrue(task2Executed.get(), "Task 2 should execute in subsequent clear");
+    }
+}