A simple bencode encoder that can handle streaming data

BencodeWriter.java

class BencodeWriter {
    static class SizedInputStream {
        public InputStream stream;
        public int size;
        public SizedInputStream(InputStream _stream,int _size) {stream = _stream;size = _size;}
    }
    public static class BencodeProducer  {
        private OutputStream out;
        public BencodeProducer(OutputStream o) {out = o;}

        public void put(Object o) throws IOException {
            // Java's poor man's pattern matching
            if (o instanceof SizedInputStream) {
                final SizedInputStream input = ((SizedInputStream) o);
                out.write((input.size +":").getBytes());
                ByteStreams.copy(input.stream,out);
            } else if (o instanceof Integer) {
                Integer i = (Integer) o;
                out.write(("i"+i+"e").getBytes());
            } else if (o instanceof Iterable) {
                Iterable iterable = (Iterable) o;
                for (Object o2 : iterable) {
                    put(o2);
                }
            }
        }
    }
}