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  • ids for this class must be manually assigned before calling save():

    Caused by: javax.persistence.PersistenceException: org.hibernate.id.IdentifierGenerationException: ids for this class must be manually assigned before calling save(): com.cjonline.ship.entity.TBLMyRecents
        at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:629)
        at org.hibernate.ejb.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:218)
        at org.jboss.ejb3.entity.TransactionScopedEntityManager.persist(TransactionScopedEntityManager.java:182)
        at com.cjonline.ship.dao.base.BaseDaoBean.save(BaseDaoBean.java:58)

    这个异常比较简单,就是实体类的id在执行save方法时没有赋值。

    可以设置主键的策略模式,常见的UUID和自增长,在EJB中如下:

    @Id
        @GenericGenerator(name = "system-uuid", strategy = "uuid")
        @GeneratedValue(generator = "system-uuid")
        @Column(length = 32,nullable=false)
        public String getId() {
            return id;
        }
    
    //-------------------------------------------------//
    
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    public String getId() {
            return id;
    }
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  • 原文地址:https://www.cnblogs.com/lbangel/p/3510565.html
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