User user=new User(); user.setId("bonnie"); user.setAge("10"); //Object转byte[] ByteArrayOutputStream byteArrayOutputStream =new ByteArrayOutputStream(); ObjectOutputStream objectOutputStream=new ObjectOutputStream(byteArrayOutputStream); objectOutputStream.writeObject(user); byte[] bytes=byteArrayOutputStream.toByteArray(); //byte[]转Object ByteArrayInputStream byteArrayInputStream=new ByteArrayInputStream(bytes); ObjectInputStream objectInputStream=new ObjectInputStream(byteArrayInputStream); User user1=(User)objectInputStream.readObject(); System.out.println(user1);