public void writeTo(DataOutput out) throws Exception {
out.writeByte(type);
switch (type) {
case DATA:
Bits.writeLong(seqno, out);
out.writeShort(conn_id);
out.writeBoolean(first);
break;
case ACK:
Bits.writeLong(seqno, out);
out.writeShort(conn_id);
break;
case SEND_FIRST_SEQNO:
Bits.writeLong(seqno, out);
break;
}
}
