Getting the HQL query result in XML format

viz7379 · **Joined:** Thu Feb 26, 2009 12:49 pm **Posts:** 4

Hello,

Hibernate version: 3.2.1

Name and version of the database you are using: SQL Server 2000

I am trying to get the hql result as XML. I use XML mapping. Any help is appreciated.

Thanks,
Viz

ethnarch · **Joined:** Tue Aug 01, 2006 9:24 pm **Posts:** 120

I might not understand you correctly, but hibernate does not serialize/convert to xml. It will always return your pojo objects. You need to do this manually or use some kind of serializing library.

You can try these.
Castor - www.castor.org
XStream - xstream.codehaus.org
JAXB - jaxb.dev.java.ne

viz7379 · **Joined:** Thu Feb 26, 2009 12:49 pm **Posts:** 4

Thanks, ethnarch. If I have to it myself, can you tell me how do I get meta data information about query. I mean what entities and what columns are selected.

Viz

viz7379 · **Joined:** Thu Feb 26, 2009 12:49 pm **Posts:** 4

Thanks, ethnarch. If I have to it myself, can you tell me how do I get meta data information about query. I mean what entities and what columns are selected. (I wanted to build result in XML dynamically).

Viz

ethnarch · **Joined:** Tue Aug 01, 2006 9:24 pm **Posts:** 120

What are you returning from your hql query raw objects or actual Pojo classes.

If you are using pojo classes. Using the xml or annotations you can use reflection to get at what the class is and then find all it's defined fields etc.

I have a project which does this already, although it's not quite finished yet but feel free to take the source code. The other catch with it is that it only works with annotations.

proselyte.sourceforge.net

viz7379 · **Joined:** Thu Feb 26, 2009 12:49 pm **Posts:** 4

I am retrieving set of objects using eager fetch and I might not be retrieving all the objects associated with the selected object. So I have to know the objects that are retrieved in the query and also I have to know all the objects actually associated with the object. And I have to generate the XML for the objects that are selected in the query. Is it similar to what you did. Any help is appreciated.

ethnarch · **Joined:** Tue Aug 01, 2006 9:24 pm **Posts:** 120

Ok so say you have mapped classes A, B and C such that in the simplest scenario we have a mapped tree that looks like this.

A{
int pkId

@OneToOne
int FKBId
}
B{
int pkId

@OneToOne
int FKCId
}
C{
int pkId

}

So C is mapped in B and B is mapped in A as OneToMany

Sometimes your queries might result in these classes being return as
A.B

Where there is no C mapped to B.

Is this correct?

This is pretty normal and I believe XStream and Castor can handle these issues. If you always know what the top of the mapped hierarchy is meaning you are always loading in Class A then this would probably be the best route to go because these are well documented and stable libraries.

I can't really give you any examples on how to use them but if you go to the sites the documentation will be there.