@Override
 public void writeExternal(ObjectOutput out) throws IOException {
   out.writeInt(size());
   for (int i = 0; i < size(); i++) {
     out.writeObject(get(i));
   }
 }
 @Override
 public void writeExternal(ObjectOutput out) throws IOException {
   out.writeInt(2);
   out.writeInt(548);
   out.writeInt(348);
   byte[] bytes = new byte[1024];
   for (int i = 0; i < 548; i++) {
     bytes[i] = 1;
   }
   out.write(bytes, 0, 548);
   bytes = new byte[1024];
   for (int i = 0; i < 348; i++) {
     bytes[i] = 2;
   }
   out.write(bytes, 0, 348);
 }