引起：org.hibernate.AnnotationException：XX 上的@OneToOne 或@ManyToOne 引用了一个未知实体：YY

Question

这里我的目标实体 User.class 存在于一个单独的 jar 文件中。

package com.aa.model;
    import javax.persistence.Entity;
    import javax.persistence.JoinColumn;
    import javax.persistence.ManyToOne;
    import javax.persistence.OneToOne;

@Entity
@Table(name = "ABC")
public class Abc implements Serializable{
---    
@OneToOne(targetEntity=com.bb.model.User.class)
    @JoinColumn(name  = "CREATED_BY")
    private User createdBy;
}
---
}

目标类：

package com.bb.model;
    import java.io.Serializable;

import javax.persistence.Entity;
import javax.persistence.Table;

@Entity
@Table(name="USER")
public class User implements Serializable {
---
}

我收到以下错误：

Caused by: org.hibernate.AnnotationException: @OneToOne or @ManyToOne on com.aa.model.Abc.createdBy references an unknown entity: com.bb.model.User
    at org.hibernate.cfg.ToOneFkSecondPass.doSecondPass(ToOneFkSecondPass.java:109)
    at org.hibernate.cfg.Configuration.processEndOfQueue(Configuration.java:1598)

Answer 1

在 Abc 类中，你写了

@OneToOne(targetEntity=com.bb.User.class)

而不是

@OneToOne(targetEntity=com.bb.model.User.class)

你也忘记了 com.bb.model 包的导入

import com.bb.model.User;