I am using Reverse Engineering (reveng.xml file) in order to generate my hbm.xml files, but I need to set the 'unsaved-value' property for an id. Does anyone know how? It doesn't seem to be covered in the manual.

Maybe someone could also explain why I need the unsaved-value in my case? A Flex client sends a newly created domain object to the server. This domain object contains a Set of other domain objects. As I am using the Spring/Flex integration framework, the Flex object arrives at the server, and the Spring/Flex framework converts the Flex int (that is used for the primary key) into a Java Integer. As it is a Flex int, the resultant Java Integer has a value of 0, this is true of all the domain objects. I save the parent object, which works fine (even though it has an Integer value of 0, and does not use the unsaved-value parameter in the mapping file). However, when the cascade tries to save the domain objects in the Set, it fails with a Spring UnexpectedRollbackException. Hibernate runs an SQL insert statement for the parent, but then tries to run an update for the child objects (which as they haven't been saved yet, causes the exception). What is the likely cause of this behavior?

I got around this by hacking the hibernate template.

In my ant script I added:



and then in the ${hibernate.auto.generator.custom.template.dir} I copied the file hbm/id.hbm.xml from hibernate-tools.jar to ${hibernate.auto.generator.custom.template.dir}/hbm. I then hacked that file so that it always puts in the unsaved-value property, and everything works fine.

I notice that the file already contains:



so if anyone knows the correct way to trigger the c2h.isUnsavedValue(property) then I would be happy to find out how!