Hi, all I am trying to serialize a StatefulKnowledgeSession into a file as a snapshot. But I got the following error: java.io.IOException: Write error at java.io.FileOutputStream.writeBytes(Native Method) at java.io.FileOutputStream.write(FileOutputStream.java:282) at java.io.BufferedOutputStream.flushBuffer(BufferedOutputStream.java:65) at java.io.BufferedOutputStream.flush(BufferedOutputStream.java:123) at java.io.ObjectOutputStream$BlockDataOutputStream.flush(ObjectOutputStream.java:1793) at java.io.ObjectOutputStream.flush(ObjectOutputStream.java:699) at java.io.ObjectOutputStream.close(ObjectOutputStream.java:720) at com.sample.test.EventDataConsumer.run(EventDataConsumer.java:44) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) However, when I serialized it to a ByteArrayOutputStream, it works well. I wrapped the stateful session in a class as a field. And I wrote writeObject and readObject methods in this class to provide custom serializing behaviour. The code is as follows: private void writeObject(ObjectOutputStream out) throws IOException { System.out.println("writing"); out.defaultWriteObject(); DroolsObjectOutputStream droolsOut = new DroolsObjectOutputStream( (OutputStream) out); droolsOut.writeObject(knowledgeBase); Marshaller marshaller = createSerializableMarshaller(knowledgeBase); marshaller.marshall(droolsOut, session); System.out.println("written"); } private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { System.out.println("read"); in.defaultReadObject(); DroolsObjectInputStream droolsIn = new DroolsObjectInputStream( (InputStream) in); this.knowledgeBase = (KnowledgeBase) droolsIn.readObject(); Marshaller marshaller = createSerializableMarshaller(knowledgeBase); session = marshaller.unmarshall(droolsIn); } private Marshaller createSerializableMarshaller(KnowledgeBase knowledgeBase) { ObjectMarshallingStrategyAcceptor acceptor = MarshallerFactory .newClassFilterAcceptor(new String[] { "*.*" }); ObjectMarshallingStrategy strategy = MarshallerFactory .newSerializeMarshallingStrategy(acceptor); Marshaller marshaller = MarshallerFactory.newMarshaller(knowledgeBase, new ObjectMarshallingStrategy[] { strategy }); return marshaller; } Out of this class, I utilized the ordinary ObjectoutputStream to serialize an instance of this class to a file. Unfortunately, I got the Exception. Any idea or response will be appreciated, Thank you very much. -- View this message in context: http://drools.46999.n3.nabble.com/Write-Error-when-Serializing-a-stateful... Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users