Hi David,
As the exception indicates Persistence is not able to find a provider
for persistence unit. Please make sure that
1. Your persistence.xml lists a provider
<provider>oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider</provider>
2. toplink-essentials.jar is available at runtime.
Thanks,
Mitesh
David Van Couvering wrote:
> Hi, all. I am trying to run Java Persistence from within an applet --
> yes, from within an applet.
>
> This is kind of urgent. If I can't get this to work, I'm going to
> have to revert to JDBC.
>
> The applet is loading derbycal.jar, which contains three Entity
> classes and META-INF/persistence.xml.
>
> When I run unit tests against derbycal standalone, Glassfish JPA is
> able to find persistence.xml and runs fine (except that it keeps
> complaining it can't find a suitable driver, but I can work on that).
>
> When I run the applet, however, it says
>
> javax.persistence.PersistenceException: No Persistence provider for
> EntityManager named derbycal
> at
> javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:89)
>
> at
> javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:60)
>
> at
> org.apache.derbyDemo.derbyCalendar.RequestManager$1.run(RequestManager.java:41)
>
> at java.security.AccessController.doPrivileged(Native Method)
> at
> org.apache.derbyDemo.derbyCalendar.RequestManager.<init>(RequestManager.java:38)
>
> at
> org.apache.derbyDemo.derbyCalendar.DerbyCalendarApplet.login(DerbyCalendarApplet.java:97)
>
>
>
> In scanning this mailing list, it appears this is a classloading problem.
>
> Does anyone know why the loader can't find META-INF/persistence.xml in
> derbycal.jar when it's loaded within an applet? How would I tell the
> applet classloader to look somewhere else? I tried putting it
> directly into the codebase directory for the applet but that didn't
> work either.
>
> Many thanks,
>
> David