What is the quickest way to serialize a Java object to Map (and parse back) with minimum code writing?

Question

Hi guys,

I have a system that entities (from database, represented as Java objects through ORM) will be read by XML-RPC clients, my existing way is to serialize them via a StructSerializer, which in its code, we read properties out from the Java object, including calling another StructSerializer to serialize/parse a property, e.g.

Surrogate parse(Map<String, Object> in) {
  String name = in.get(Surrogate.NAME, String.class);
  ...
}

Map<String, Object> serialize(Surrogate in) {
  out.put(Surrogate.ID, in.getId());
  out.put(Surrogate.USER, userSerializer.serialize(in.getUser()))
}

What I am looking now is to eliminate/automate/minimize writing such code. Also, XML-RPC-compatible is not really the issue.

Thanks a lot.

Edited:

To elaborate further, XML conversion is handled by Apache XML-RPC, all I need is to dump in a Map for it to work on. What I need now is a unified/well-accepted way to convert Java objects to Map.

Answer 1

I like XStream for this kind of work - http://xstream.codehaus.org/

All you have to do is annotate your classes and feed them into the XStream serializer/deserializer. You may want to annotate specific fields to tune the output, but you usually don't have to.

Answer 2

If you don't need to be compatible, there are a number of options: XMLEncoder, XStream, Castor. They all require very little code to write, unless you need something fancy. XMLEncoder is included in the JRE, others are additional libraries.

Answer 3

I refined my search and found: http://stackoverflow.com/questions/739689/how-to-convert-a-java-object-bean-to-key-value-pairs-and-vice-versa

That suggests BeanUtils as a good solution.