This is a combination of JPA and transaction semantics that I'm not clear on.
If I use a sequence table, my object's PK will be set after calling em.persist(obj). If I use IDENTITY, it's null. Doesn't matter if it's Derby or MySQL (nor should it but I just wanted to rule out the DB).
Hmm. I call em.flush() and em.refresh(obj) to get back a usable identity to tell my client.
However, when using NetBeans' automatic entity generation thingy with JAX-RS, things don't work of course.
When I create an object using curl, the location header returned is incorrect in two ways and I'm not sure why.
1. If I don't tweak the generated code (resolveEntity is where I chose to put the em.flush() and em.refresh() calls), the location header comes back as null making it impossible to have something URN-like for chasing the resource down.
2. The Location header also doesn't include the name of the collection where said entity could be looked up again.
Has anyone else noticed this? Is the automatic generation worth pursuing or is it not considered appropriate for production? It seems like decent code and technique -- I can't be the first to have run across this issue but I haven't found any updates to NetBeans that would fix it.
I really don't want to add a DAO layer -- it's so repulsive, but I don't see an alternative since every entity needs to be flushed and refreshed to be useful in a web service or page.
thanks,
greg
curl -v -X POST --data-binary @asite.xml -H"Content-Type: application/xml" -H"Accept: application/xml"
http://localhost:8080/com.ggerard.gravity/resources/sites
* About to connect() to localhost port 8080 (#0)
* Trying 127.0.0.1... connected
* Connected to localhost (127.0.0.1) port 8080 (#0)
> POST /com.ggerard.gravity/resources/sites HTTP/1.1
> User-Agent: curl/7.19.6 (i386-apple-darwin10.0.0) libcurl/7.19.6 zlib/1.2.3
> Host: localhost:8080
> Content-Type: application/xml
> Accept: application/xml
> Content-Length: 615
>
< HTTP/1.1 201 Created
< X-Powered-By: Servlet/3.0
< Server: GlassFish v3
< Location:
http://localhost:8080/com.ggerard.gravity/resources/1/
< Content-Length: 0
< Date: Mon, 05 Apr 2010 05:41:07 GMT
<
* Connection #0 to host localhost left intact
* Closing connection #0