Java Pattern for generating and parsing data in stream

I have certain protocol that I need to parse or generate. The parsing takes an InputStream and produce different type of objects depending the byte stream. The generator takes different inputs and spit out an OutputStream that allows writing to a target stream. Before reading / writing to the stream there might be some header variables that needs to be initialized.

For code right now looks something like follows:

// Parser.
DataX parsed = DataX.parse(new ByteInputStream(new byte [] {..}));
// Access short field of DataX.
System.out.println(parsed.getX() + parsed.getY()); // data in the header.
// Access some long field by spitting InputStream.
System.out.println(parsed.buildInputStream().readFully()); // data as bytes.

// Generator.
OutputStream outstream = 
   DataX.Generator(new FileOutputStream('output')).setX(x).setY(y).build();
// Write data.
outstream.write(data);

DataX extends a class Data that implements two methods deserialize and serialize as abstract method which will eventually be called somewhere inside parse() and Generator().

This is a self-made design pattern, so I would like to ask if this makes sense and whether there is a more Java-ist way to do this kind of thing ?