Hibernate：如何在其他实体中加入一个实体的列表？（引用的属性未知）

Question

@Entity
@Table(name = "Case")
public class Case 
  @Enumerated(EnumType.STRING)
  @OneToOne(mappedBy = "case", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
  public List<Ghoda> getGhodaHistory() {
    return ghodaHistory;
  }

  public void setGhodaHistory(List<Ghoda> ghodaHistory) {
    this.ghodaHistory= ghodaHistory;
  }

@Entity
@Table(name = "Ghoda")
public class Ghoda{
  @OneToOne
  @JoinColumn(name = "case_ID")
  public Case getCase() {
      return case;
  }

  public void setCase(Case case) {
      this.case= case;
  }  
}

Caused by: org.hibernate.AnnotationException: Unknown mappedBy in: de.bokla.model.Case.ghodaHistory, referenced property unknown: java.util.List.case

我不是很精通hibernate，我是根据现有的代码创建的，但是找不到错误所在，有没有人能建议一下如何解决这个问题呢？

Answer 1

您需要通过以下方式使用@OneTomany映射

@Entity
@Table(name = "Case")
public class Case 

  @OneToMany(mappedBy = "case", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
  public List<Ghoda> getGhodaHistory() {
    return ghodaHistory;
  }

  public void setGhodaHistory(List<Ghoda> ghodaHistory) {
    this.ghodaHistory= ghodaHistory;
  }

}

@Entity
@Table(name = "Ghoda")
public class Ghoda{

  @ManyToOne
  @JoinColumn(name = "case_ID")
  public Case getCase() {
      return case;
  }

  public void setCase(Case case) {
      this.case= case;
  }

}

最简单的方法

@Entity
@Table(name = "Case")
public class Case 

  @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY)
  @JoinColumn("case_ID")
  public List<Ghoda> getGhodaHistory() {
    return ghodaHistory;
  }

  public void setGhodaHistory(List<Ghoda> ghodaHistory) {
    this.ghodaHistory= ghodaHistory;
  }

}

@Entity
@Table(name = "Ghoda")
public class Ghoda{

}

https://stackoverflow.com/A/37542849/3405171