Caused by: javax.persistence.PersistenceException: Illegal argument
at org.datanucleus.jpa.NucleusJPAHelper.getJPAExceptionForNucleusException(NucleusJPAHelper.java:260)
at org.datanucleus.jpa.EntityTransactionImpl.commit(EntityTransactionImpl.java:122)
at org.datanucleus.store.appengine.jpa.DatastoreEntityTransactionImpl.commit(DatastoreEntityTransactionImpl.java:55)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:456)
... 86 more
Caused by: java.lang.IllegalArgumentException: can't operate on multiple entity groups in a single transaction. found both Element {
type: "Options"
id: 36
}
and Element {
type: "Options"
id: 37
}
因为GAE只支持一个事务操作一个实体.
这里讲到了很多GAE开发中的注意点,值得参考:http://www.cnblogs.com/senzjx/archive/2009/09/20/1570669.html
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