fix(java): support copy of non-serializable JDK classes such as java.lang.Package

java/fory-core/src/main/java/org/apache/fory/platform/GraalvmSupport.java

@@ -39,6 +39,7 @@
 import org.apache.fory.serializer.JavaSerializer;
 import org.apache.fory.serializer.JdkProxySerializer;
 import org.apache.fory.serializer.LambdaSerializer;
+import org.apache.fory.serializer.NonSerializableSerializer;
 import org.apache.fory.serializer.ObjectSerializer;
 import org.apache.fory.serializer.ObjectStreamSerializer;
 import org.apache.fory.serializer.PrimitiveArraySerializers;
@@ -140,6 +141,7 @@ public class GraalvmSupport {
     registerDefaultSerializerClass(ObjectStreamSerializer.class);
     registerDefaultSerializerClass(JavaSerializer.class);
     registerDefaultSerializerClass(ObjectSerializer.class);
+    registerDefaultSerializerClass(NonSerializableSerializer.class);
   }
 
   /** Returns true if current process is running in graalvm native image build stage. */

java/fory-core/src/main/java/org/apache/fory/resolver/ClassResolver.java

@@ -127,6 +127,7 @@
 import org.apache.fory.serializer.JdkProxySerializer;
 import org.apache.fory.serializer.LambdaSerializer;
 import org.apache.fory.serializer.LocaleSerializer;
+import org.apache.fory.serializer.NonSerializableSerializer;
 import org.apache.fory.serializer.NoneSerializer;
 import org.apache.fory.serializer.ObjectSerializer;
 import org.apache.fory.serializer.OptionalSerializers;
@@ -1498,9 +1499,8 @@ public Class<? extends Serializer> getSerializerClass(Class<?> cls, boolean code
         }
       }
       if (config.checkJdkClassSerializable()) {
-        if (cls.getName().startsWith("java") && !(Serializable.class.isAssignableFrom(cls))) {
-          throw new UnsupportedOperationException(
-              String.format("Class %s doesn't support serialization.", cls));
+        if (cls.getName().startsWith("java") && !Serializable.class.isAssignableFrom(cls)) {
+          return NonSerializableSerializer.class;
         }
       }
       if (ScalaTypes.SCALA_AVAILABLE && ReflectionUtils.isScalaSingletonObject(cls)) {
@@ -1513,8 +1513,6 @@ public Class<? extends Serializer> getSerializerClass(Class<?> cls, boolean code
         }
       }
       if (isCollection(cls)) {
-        // Serializer of common collection such as ArrayList/LinkedList should be registered
-        // already.
         serializerClass = ChildContainerSerializers.getCollectionSerializerClass(cls);
         if (serializerClass != null) {
           return serializerClass;

java/fory-core/src/main/java/org/apache/fory/serializer/NonSerializableSerializer.java

@@ -0,0 +1,52 @@
+/*
+ * 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.fory.serializer;
+
+import org.apache.fory.context.ReadContext;
+import org.apache.fory.context.WriteContext;
+import org.apache.fory.resolver.TypeResolver;
+
+/**
+ * Serializer for non-Serializable JDK classes. Binary serialization is unsupported — {@link
+ * #write}/{@link #read} throw {@link UnsupportedOperationException} — while copy reuses {@link
+ * AbstractObjectSerializer}'s field-copy implementation.
+ *
+ * <p>Distinct from {@link CopyOnlyObjectSerializer}, which blocks serialization for
+ * registration-security reasons (remediable by registering the class). Here serialization is
+ * intrinsically unsupported and not remediable by registration, so the failure semantics differ
+ * deliberately.
+ */
+public final class NonSerializableSerializer<T> extends AbstractObjectSerializer<T> {
+  public NonSerializableSerializer(TypeResolver typeResolver, Class<T> type) {
+    super(typeResolver, type);
+  }
+
+  @Override
+  public void write(WriteContext writeContext, T value) {
+    throw new UnsupportedOperationException(
+        String.format("Class %s doesn't support serialization.", type.getName()));
+  }
+
+  @Override
+  public T read(ReadContext readContext) {
+    throw new UnsupportedOperationException(
+        String.format("Class %s doesn't support serialization.", type.getName()));
+  }
+}

java/fory-core/src/test/java/org/apache/fory/ForyCopyTest.java

@@ -79,13 +79,16 @@
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.regex.Pattern;
 import org.apache.fory.collection.LazyMap;
+import org.apache.fory.config.Language;
 import org.apache.fory.context.CopyContext;
 import org.apache.fory.context.ReadContext;
 import org.apache.fory.context.WriteContext;
 import org.apache.fory.exception.ForyException;
+import org.apache.fory.exception.SerializationException;
 import org.apache.fory.resolver.TypeResolver;
 import org.apache.fory.serializer.EnumSerializerTest;
 import org.apache.fory.serializer.EnumSerializerTest.EnumFoo;
+import org.apache.fory.serializer.NonSerializableSerializer;
 import org.apache.fory.serializer.Serializer;
 import org.apache.fory.serializer.collection.ChildContainerSerializersTest.ChildArrayDeque;
 import org.apache.fory.serializer.collection.SynchronizedSerializersTest;
@@ -454,4 +457,29 @@ public void testComplexCollectionCopy() {
       assertEquals(fory.copy(collectionFields).toCanEqual(), collectionFields.toCanEqual());
     }
   }
+
+  @Test
+  public void testCopyNonSerializableJdkClass() {
+    Fory fory = Fory.builder().withLanguage(Language.JAVA).requireClassRegistration(false).build();
+    Class<? extends Serializer> serializerClass =
+        fory.getTypeResolver().getSerializerClass(java.lang.Package.class);
+    Assert.assertSame(serializerClass, NonSerializableSerializer.class);
+  }
+
+  @Test
+  public void testSerializeNonSerializableJdkClassStillThrows() {
+    Fory fory =
+        Fory.builder()
+            .withLanguage(Language.JAVA)
+            .withRefCopy(true)
+            .requireClassRegistration(false)
+            .build();
+    try {
+      fory.serialize(String.class.getPackage());
+      Assert.fail("Expected serialization of java.lang.Package to fail");
+    } catch (SerializationException e) {
+      Assert.assertTrue(e.getCause() instanceof UnsupportedOperationException);
+      Assert.assertTrue(e.getMessage().contains("doesn't support serialization"));
+    }
+  }
 }