java.sql.Date, Seam-GWT remoting with EJB3/hibernate/JPA

[dhartford]

Hey all,
After a lot of digging, finally found where I am having an issue with some DTO transports using the SEAM-GWT remoting.

First, the (not useful) error on the client/browser side:
=========================

com.google.gwt.user.client.rpc.IncompatibleRemoteServiceException: This application is out of date, please click the refresh button on your browser

com.google.gwt.user.client.rpc.IncompatibleRemoteServiceException

=========================

Second, where the problem is originating from:
===========
DTO.java:

 @Temporal(TemporalType.DATE)
 private java.util.Date dateField;

===========


And third, the actual class that is returned (by hibernate):
============

datefield type:java.sql.Date

============

What is returned by the JPA layer, in this case Hibernate, is causing problems within SEAM when trying to transfer the DTO to the GWT client side.

Manually creating the DTO (without hibernate) with a regular java.util.Date works correctly, but changing it to java.sql.Date causes problems as seen in the error above.

Tested with jboss 4.2.1, seam 2.0.0.GA (GWT 1.4.60).

HTH,
-D

[dhartford]

actually sending java.sql.Date over the JSON wire:

//EX

["com.domain.app.model.SimpleDTO/3809314052","java.sql.Date/20738045"]

[dhartford]

discussion on problem:


http://groups.google.com.ec/group/Google-Web-Toolkit/browse_thread/thread/ee868c16992937ac/0e2288691663d975

english:
http://translate.google.com/translate?hl=en&sl=es&u=http://groups.google.com.ec/group/Google-Web-Toolkit/browse_thread/thread/ee868c16992937ac/0e2288691663d975&sa=X&oi=translate&resnum=2&ct=result

[dhartford]

another discussion here

http://groups.google.com/group/Google-Web-Toolkit/tree/browse_frm/month/2007-04/f7a5a1f03a87cc99?rnum=71&_done=%2Fgroup%2FGoogle-Web-Toolkit%2Fbrowse_frm%2Fmonth%2F2007-04%3F


and sample workaround:

/**
* utility method to re-process DTO's to make sure that the dates
* are explicitly converted to java.util.Date.
*/
 private SimpleDTO[] convertSqlDates(SimpleDTO[] myarray){
 //DRH cloning would be safer, but private anyway.
 for (int i = 0; i < myarray.length; i++) {
 SimpleDTO simpleDTO = myarray;
 if(simpleDTO.getDateField() != null){
 simpleDTO.setDateField(new java.util.Date(simpleDTO.getDateField().getTime()));
 }
 }
 return myarray;
 }

NOTE: I've tried changing the getter/setters and this will NOT work for hibernate/JPA, you need to change it after retrieval but before submitting over the wire.

Another NOTE: I've tried changing the GWTService, GWT13Service, GWT14Service classes in SEAM to modify this behavior, but I can't seem to find a good fix, so the workaround seems like the only option for now.