问题
I got this error which according to Apache Support is an issue relating with Glassfish rather than OpenJPA:
java.lang.IllegalStateException: WEB9031: WebappClassLoader unable to load resource [org.apache.openjpa.util.LongId], because it has not yet been started, or was already stopped
The stacktrace is:
Caused by: java.lang.IllegalStateException: WEB9031: WebappClassLoader unable to load resource [org.apache.openjpa.util.LongId], because it has not yet been started, or was already stopped
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1410)
at org.glassfish.web.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1368)
at com.ckd.model.BookModel.pcNewObjectIdInstance(BookModel.java)
at org.apache.openjpa.enhance.PCRegistry.newObjectId(PCRegistry.java:138)
at org.apache.openjpa.meta.MetaDataRepository.processRegisteredClass(MetaDataRepository.java:1693)
at org.apache.openjpa.meta.MetaDataRepository.processRegisteredClasses(MetaDataRepository.java:1643)
... 112 more
Has anyone come across this before and how to resolve it? I have been stuck on this issue for the last several days.
Another of my post related to this issue can be found here: JSF 2: h:link and getrowdata.
回答1:
The above error relates to a problem with the OpenJPA enhancer. When you execute Sun's JDK the OpenJPA's dynamic enhancer starts by default. This action, in turn, stuffs up Glassfish's classloader class - hence, the WEB9031 error.
For those who experience this same issue, a simple workaround is to do the enhancement at build time - which I did in ANT with org.apache.openjpa.ant.PCEnhancerTask - and add this property to your persistence.xml to shut off the dynamic enhancer: <property name="openjpa.DynamicEnhancementAgent" value="false"/>.
Also, it wouldn't hurt to throw this in your persistence.xml as well <property name="openjpa.RuntimeUnenhancedClasses" value="unsupported" />.
来源：https://stackoverflow.com/questions/5622436/jsf-2-openjpa-2-glassfish-3-1-web9031-error