【hibernate错误】An association from the table refers to an unmapped class

完整错误提示

Caused by: org.hibernate.MappingException: An association from the table T_MATERIAL_IN_DETAIL refers to an unmapped class: com.hcepms.model.cost.contract.ContractDetail
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.secondPassCompileForeignKeys(InFlightMetadataCollectorImpl.java:1837)
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.secondPassCompileForeignKeys(InFlightMetadataCollectorImpl.java:1808)
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1627)
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:278)
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
    at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
    at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:692)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:727)
    at org.springframework.orm.hibernate5.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:416)
    at org.springframework.orm.hibernate5.LocalSessionFactoryBean.afterPropertiesSet(LocalSessionFactoryBean.java:401)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1642)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1579)
    ... 35 more