Does the book deals with Spring Dm assuming that the server used is Spring DM Server (now aka Virgo) or is agnostic of any specific server?
Specifically, Dm Server allows using JPA easily with PAR Archive, but this archive format is specific to DM Server.
Does your book present the use of JPA in a portable way?
Andy Piper
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Hello
Gildas Cuisinier wrote:Does the book deals with Spring Dm assuming that the server used is Spring DM Server (now aka Virgo) or is agnostic of any specific server?
The book is almost entirely agnostic to the specific server used and deals with the specifics of Spring DM itself. We talk about dm Server a little, but not a great deal.
Gildas Cuisinier wrote:Specifically, Dm Server allows using JPA easily with PAR Archive, but this archive format is specific to DM Server.
Does your book present the use of JPA in a portable way?
Yes, we discuss how to use JPA without the need for invoking any proprietary extensions such as the PAR format.
To complete what Andy said, we deal with Hibernate JPA, OpenJPA and EclipseLink. The main problems when trying to use JPA within an OSGi container consist in the mapped clas visibility and the use of load time weaving to intrument managed entities when required.
The first point is directlty adresses by Spring DM with its thread context classloader management at service level.
The second point can be much more problematic since load time weaving isn't supported by all OSGi containers but the great news is that not all JPA implementations require this feature: Hibernate doesn't need it and OpenJPA leaves you the choice... Moreover, when load time weaving is required within Equinox container, you can use Equinox Aspects and its adapter for Spring.
Thierry
subject: * Welcome Arnaud Cogoluegnes, Thierry Templier & Andy Piper