out.writeObject(messageID);
out.writeUTF((String)messageID);
   public void writeExternal(ObjectOutput out) throws IOException   {            out.writeObject(messageID);      out.writeBoolean(reliable);      out.writeLong(expiration);      out.writeLong(timestamp);      writeMap(out, headers);      out.writeBoolean(redelivered);      out.writeInt(priority);      out.writeInt(deliveryCount);      out.writeLong(ordering);   }