log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).
log4j:WARN Please initialize the log4j system properly.
org.hibernate.MappingException: Unsupported cascade style: save_update
at org.hibernate.engine.CascadeStyle.getCascadeStyle(CascadeStyle.java:269)
at org.hibernate.mapping.Property.getCascadeStyle(Property.java:95)
at org.hibernate.tuple.PropertyFactory.buildStandardProperty(PropertyFactory.java:132)
at org.hibernate.tuple.entity.EntityMetamodel.<init>(EntityMetamodel.java:171)
at org.hibernate.persister.entity.AbstractEntityPersister.<init>(AbstractEntityPersister.java:434)
at org.hibernate.persister.entity.SingleTableEntityPersister.<init>(SingleTableEntityPersister.java:109)
at org.hibernate.persister.PersisterFactory.createClassPersister(PersisterFactory.java:55)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:226)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1294)
at com.booklib.service.BusinessService.<clinit>(BusinessService.java:27)
Exception in thread "main" java.lang.NullPointerException
at com.booklib.service.BusinessService.saveReaderAndBookAndBorrowInfo(BusinessService.java:35)
at com.booklib.service.BusinessService.main(BusinessService.java:115)
方案：
org.hibernate.MappingException: Unsupported cascade style: save_update save-update笔误