I'm facing the task of migrating someone's EJB2 model to EJB3. One of the things that was done was persisting a Map (containing <String, Object>) by serializing it to a binary column. I trying to figure out how to map this in EJB3. The EJB2 definition looks like this:

/**
* @ejb.interface-method
* @ejb.persistence column-name="properties"
*/
public abstract Map getProperties();

I hoped this EJB3 mapping would do the trick:

@Embedded
private Map<String,Object> properties;

But all entities have null instead of a list (which I know is filled).

Any suggestions?

Figured it out myself. For those interested, below are the EJB3 implementations:

@Override
public Map<String, Object> getProperties() {
try {
// deserialize
ObjectInputStream ois = new ObjectInputStream( new ByteInputStream(properties, properties.length) );
Object o = ois.readObject();
MarshalledValue mv = (MarshalledValue)o;
o = mv.get();
HashMap<String, Object> m = (HashMap<String, Object>)o;
return m;
}
catch (IOException e) {
throw new RuntimeException(e);
}
catch (ClassNotFoundException e) {
throw new RuntimeException(e);
}
}

@Override
public void setProperties(Map<String, Object> properties) {
try {
// first create a JBoss MarshalledValue
MarshalledValue mv = new MarshalledValue(properties);

// serialize
ByteOutputStream bos = new ByteOutputStream();
ObjectOutputStream oos = new ObjectOutputStream( bos );
oos.writeObject(mv);
oos.flush();
byte[] bs = bos.getBytes();
this.properties = bs;
}
catch (IOException e) {
throw new RuntimeException(e);
}
}