int b=instream.read(); if(b == 1) { arg=new PingRsp(); arg.readFrom(instream); }
arg=(PingRsp)Util.readStreamable(PingRsp.class, instream);
    public void readFrom(DataInputStream instream) throws IOException, IllegalAccessException, InstantiationException {        type=instream.readByte();        int b=instream.read();        if(b == 1) {            arg=new PingRsp();            arg.readFrom(instream);        }    }