public void getResource(Mms msg) {
   ByteBuffer buffer = ByteBuffer.wrap(this.getRaw());
   int count = buffer.getInt();
   List<MmsPart> parts;
   Mms mms = msg;
   // get parts
   if (RawTransUtil.LENGTH_NULL != count) {
     parts = new ArrayList<MmsPart>(count);
     for (int i = 0; i < count; i++) {
       MmsPart part = new MmsPart();
       part.readRaw(buffer);
       parts.add(part);
     }
   } else {
     parts = null;
   }
   mms.setParts(parts);
 }